Is there a better type of experiment than this cookie experiment? Sorry to all of you scientists out there, but I win. I've seen a lot of rules around cookie baking. The most common being that you MUST chill your dough before cooking, and you shouldn't using completely melted butter. This got me thinking - does following certain cookie rules actually make a difference?
Well it turns out the answer is yes. Quite a significant difference actually.
I baked over 80 cookies for this cookie experiment - and I probably ate at least 10% of those cookies 🙂
This experiment took a fair bit of prep, and pretty much a whole day of baking. So I decided to combine it with my last week at work and get my office friends involved in this taste test as part of my goodbye. My kids named themselves senior taste testers too, and took the job very seriously!! All-in-all I had 17 taste testers. I asked my volunteers to vote for their favourite cookie, and also to let me know their least favourite (although 4 people didn't let me know their least favourite)
I used the recipe from my Classic Chewy Chocolate Chip Cookies post as my control recipe (which I originally got from Sally's Baking addiction). This recipe calls for the following ingredients and rules:
Ingredients:
- 280g plain flour
- 1 tsp baking soda
- 1 and ½ tsp cornflour
- ½ tsp salt
- 170g unsalted butter almost fully melted (it’s better not to completely melt it as it can make the cookies greasy)
- 150g light brown muscavado sugar
- 100g granulated sugar
- 1 large egg
- 1 egg yolk
- 2 tsp vanilla extract (or vanilla paste)
- 180g good quality chocolate chips
Rules:
- Ensure your butter is very soft, but not completely melted
- Refrigerate the cookie dough for at least two hours
- Use a mix of brown and white sugar
- I also baked each cookie for exactly 12 minutes, with the exception of the ones I baked from frozen - I gave these 13 minutes.
(see the original cookie post for instructions on how to make)
For the experiment, I made one simple change to each of the 8 further batches of cookies I made. These changes were:
- Replaced baking soda with baking powder
- Baked the cookie dough balls from frozen (i.e go through the refrigeration stage, roll the dough into balls, and then freeze)
- Baked the cookies without refrigerating the dough
- Baked the cookies after refrigerating overnight - rather than for 2 hours
- Used all brown sugar (i.e 250g brown sugar) rather than a mix of brown and white sugar
- Used 15% more flour (the idea behind this was to see if I'd get a thicker cookie)
- Used completely melted butter instead of very soft/almost melted butter
- Used all white sugar (i.e 250g white sugar) rather than a mix of brown and white sugar
Here's a close up and explanation of the results:
1. Replaced baking soda with baking powder:
Replacing the baking soda with baking powder produced cookies that had a had a domed effect in the middle, with the outside edges being very flat and crunchy. They were still tasty cookies, but they weren't chewy at all. 1 person voted for these cookies as their favourite.
2. Baked the cookie dough balls from frozen (i.e go through the refrigeration stage, roll the dough into balls, and then freeze)
I admit, I cooked these cookies for 1 minute longer than the others, as I expected it to need longer with it being cooking from frozen. As it turns out, they don't need longer. 12 minutes would have been just fine (I discovered this later - after further experimentation with a number of cookie dough balls that I decided to freeze for 'emergencies'). These cookies came out of the oven very puffed up and smooth. They sank a little during cooling and went a little rippled as they sank. These cookies had loads of flavour. They were crunchy on the outside and chewy in the middle. 2 people voted for these cookies as their favourite.
3. Baked the cookies without refrigerating the dough
These cookies, although quick to make, were definitely the worst by far. They were firm, crumbly, had a very cracked appearance on top, and a bit of a strange looking shine to them. There was no depth of flavour to these cookies. It was also much harder to shape them into balls before baking. When you refrigerate your cookie dough, it goes a lot firmer, enabling you to mould the cookie dough into a ball in your hands. If you don't refrigerate, you're dealing with a sloppy batch of cookie dough. This meant my hands were sticky, and the dough was basically splodged onto the baking mat. In an attempt to make these ones easier to handle, I also wet my hands before trying to form a couple of them into balls. Interestingly, I found that doing this meant that the resulting cookies didn't have the cracked, shiny appearance. However, they still tasted bland. You can see on this picture that the top cookie was formed with dry hands, and the bottom two were formed using wet hands. 1 person voted for these cookies as their favourite. 11 people voted for these cookies as their least favourite.
4. Baked the cookies after refrigerating over night - rather than for 2 hours
These cookies were soft and chewy with lots of flavour. Not much else to say! 5 people voted for these cookies as their favourite. 1 person voted for these cookies as their least favourite.
5. Used all brown sugar (i.e 250g brown sugar) rather than a mix of brown and white sugar
Definitely one of my favourites. These cookies had a real caramel flavour, they were chewy on the inside, crisp on the outside and were very tasty. The brown sugar produced a darker appearance than the other cookies. 4 people voted for these cookies as their favourite.
6. Used 15% more flour
Using more flour produced a thicker cookie that spread less during baking. They were a little drier than the control cookie. They had less flavour, and a slight floury/cloying texture. Visually, they were probably the most appealing during to their puffy, thick appearance. 2 people voted for these cookies as their favourite.
7. Used completely melted butter instead of very soft/almost melted butter
These cookies were tasty and very soft on the inside. They did have slightly more of a greasy texture than the control. They also spread more during baking than any of the other cookies. 1 person voted for these cookies as their favourite.
8. Used all white sugar (i.e 250g white sugar) rather than a mix of brown and white sugar
These cookies were reasonably thick and very pale looking. They were chewy and soft, although they were quite dry at the edges. As expected, they had less of a caramel flavour than the control cookies. No-one voted for these cookies as their favourite.
Finally, here's the control cookie
An all round, tasty, soft, chewy cookie. 1 person voted for these cookies as their favourite. 1 person voted for these cookies as their least favourite.
Conclusion:
The overall favourite from the taste experiment was cookie number 4 (where the cookie dough had been refrigerated overnight). The overnight refrigeration really allowed those flavours to fully develop. Cookie 5 (all brown sugar) came a close second.
Based on these results (and if you like a very flavoursome, soft and caramelly cookie) it may well be worth making your cookies using only brown sugar, and refrigerating the dough overnight.
For me, I'll also be ensuring I have a good stock in the freezer so I can put one in the oven whenever the craving strikes!
What do you think? Have you done any similar experimentation? Which one do you think you'd choose as favourite?
As a reminder, here's the basic control recipe (however the experiment results suggest you use just brown sugar instead of a mix of brown and white, and also chill the mixture overnight or cook the dough balls from frozen):
The Cookie Experiment Recipe:

Cookie Experiment
Ingredients
- 280 g (2 ⅓ cups) plain (all-purpose) flour
- 1 tsp baking soda
- 1 ½ tsp cornflour
- ½ tsp salt
- 170 g (¾ cup + 1 tsp) unsalted butter almost fully melted - it’s better not to completely melt it as it can make the cookies greasy
- 150 g (¾ cup) light brown muscavado sugar
- 100 g (½ cup) granulated sugar
- 1 large egg
- 1 egg yolk
- 2 tsp vanilla extract - or vanilla paste
- 180 g (1 cup + 1 tbsp) good quality chocolate chips
INSTRUCTIONS
- In a bowl, mix together your flour, baking soda, cornflour and salt. Set aside.280 g (2 ⅓ cups) plain (all-purpose) flour, 1 tsp baking soda, 1 ½ tsp cornflour, ½ tsp salt
- In a large bowl, whisk together the butter and the two sugars until thoroughly combined.170 g (¾ cup + 1 tsp) unsalted butter almost fully melted, 150 g (¾ cup) light brown muscavado sugar, 100 g (½ cup) granulated sugar
- Add the egg, egg yolk and vanilla extract and whisk again until combined. Add the flour mixture and mix together using a wooden spoon.1 large egg, 1 egg yolk, 2 tsp vanilla extract
- Finally pour in your chocolate chips, reserving 1 tbsp of them to put on top later. Mix everything together so you get an even distribution of chocolate chips.180 g (1 cup + 1 tbsp) good quality chocolate chips
- Then place some clingfilm over the bowl and chill in the refrigerator for at least 2 hours (and up to 3 days). It’s very important to chill the dough, so you don’t get flat cookies that spread all over your baking tray upon baking.
- When you’re ready to bake the cookies, pre-heat the oven to 160C/325F (fan).
- Line 3 large baking trays with baking parchment or a silicone baking mat.
- Take the cookie dough out of the refrigerator and scoop out a heaped tablespoon full (you may want to weigh out the dough to get even sized cookies. 2 oz/55g of dough makes a good sized cookie. You’ll get about 16-18 cookies out of this). Roll the dough into a ball with your hands, and place on you baking sheet. Repeat until you have used all of the dough. Make sure your dough balls are a good distance apart on the baking sheet as they will spread. I tend to put 6 or 7 cookies on each baking sheet.
- Place in the oven and cook for 10-13 minutes, depending on whether you like your cookies soft and chewy or a bit more crisp.
- Take out of the oven and push the reserved chocolate chips gently into the hot cookies. Leave to cool on the baking tray for 10 minutes before gently lifting off with a spatula and cooling completely on a cooling rack.
✎ Notes
Nutrition
apuginthekitchen says
Really impressive, comprehensive and done in a scientific manner. You are so right, there are huge differences in cookies when prepared differently even down to the temp of the butter, I love using all brown sugar in my chocolate chip recipe.
Nicky Corbishley says
Yes, I think I was most amazed about the difference in using baking soda and baking powder. A real significant outcome. I was hoping to get it up on foodgawker, but they don't want to take it with the words scrawled all over the blackboard 🙁
Margot @ Gather and Graze says
Fabulous experiment Nicky - I love your dedication… just wish I'd been able to be one of your taste-testers! 🙂 The Fiesta Friday crowd will love reading of your results!
Nicky Corbishley says
Ha ha thanks Margot. The dedication isn't hard when it comes to cookies 🙂
spiceinthecity says
Love this experiment and all the details! Gonna come back to this post next time I'm making cookies 🙂
Nicky Corbishley says
Thanks Naina, brown sugar ones certainly got the thumbs up!
saucygander says
Wow, that is a serious scientific experiment!! I've made cookies that were refrigerated for between 1 and 3 days, and there was a definite change in texture.
This will be a really handy reference, bookmarked. Thank you for sharing your results with Fiesta Friday! I hope there are some cookies we can eat too? 🙂
Nicky Corbishley says
No problem, glad you liked it 🙂 Of course - plenty of virtual cookies coming your way!!
Butter, Basil and Breadcrumbs says
Oh my gosh...Nicky. This post is so much fun!! I love it! You must have had a blast doing this, and your taste testers must have LOVED it!
I've never done an experiment like this...and now I'm wondering why I haven't... but I was on a quest for the most perfect chocolate chip cookie recipe for about 6 months.
I'll be trying yours for sure! This is brilliant. Simply brilliant. LOVE. <3
Nicky Corbishley says
It was serious fun Prudy. I think my kids had the best time of all with it 🙂
Sinfully Tempting says
Love this experiment, very interesting results...thank you! )
Nicky Corbishley says
Thanks for coming to take a look 🙂
Michelle says
I love this post! I always refrigerate my dough before baking but I make the balls before i refrigerate them so I don't avoid the mess unfortunately!
Nicky Corbishley says
It really is messy isn't it! Wetting my hands seemed to help when the dough was sticky. I didn't try wetting my hands and then refrigerating the dough, but that might be worth a try.
Jess says
What a great informative post! Thanks for sharing this at the FF party 😀
Nicky Corbishley says
Thanks Jess, glad you liked it 🙂
chefjulianna says
Wow, I completely admire your dedication to this delicious experiment!! What will you do next? Maybe we can vote on that too! 😀 I vote for #5! I just wish I could eat one right now! 🙂
Nicky Corbishley says
Ha ha I'm open to suggestions on the next experiment!
strictlydelicious says
Thanks for all that work for our benefit! I really enjoyed reading about your experiment, and I learned quite a bit! So you liked the "refrigerated overnight" cookies better than the "frozen cookies?"
Nicky Corbishley says
Thanks Lina. Yes, the refrigerated ones were great. It's just too handy to have a load of frozen cookie balls in the freezer though, and they come very close to the refrigerated version!
sarahgiebens says
I really really like your experiment! Thank you so much for this! Now we'll be able to bake the (for us) perfect cookie 😀
The cookies loo great!
Happy Fiesta Friday!
Nicky Corbishley says
Thanks for stopping by Sarah, glad you liked the post. Happy FF 🙂
HostessAtHeart says
Wow, what a great way to get personal knowledge of the science of the cookie! I would have gained 10 pounds doing it but would have enjoyed every bit of it!
Nicky Corbishley says
My jeans do feel a little tighter, but it's all in the name of science 🙂
radhikasethi says
Such a great experiment no one can say no to.. I would have loved to be the tester 😉 Such a great post and shall bookmark it for future reference.
happy Fiesta Friday 🙂
Nicky Corbishley says
Thanks Radhika, i'd have loved to have all the FF gang over for testing!! Happy Fiesta Friday to you too 🙂
A Home Cook says
Back in the day, when i was younger and my hands were colder, always cold, I never needed to let the dough chill. It made no difference. Maybe it's time I tested it again.
Great experiment. I'm sure my kids would love it. Happy Fiesta Friday
Nicky Corbishley says
Ooh yes you should try that again. That chilling time is hard going when you're desperate for a cookie!
Kaila511 says
We experiment all the time over here, but mainly with different egg substitutes. Or one time, I tried a ridiculous number of dairy free milks on brownies (chocolate almond, almond, hemp, rice, etc.) This is such a cool idea though, I might have to try it out when I have A TON of time someday! Thanks for sharing the results. It was cool that you had such a big population to test on. 🙂
Nicky Corbishley says
Glad you liked it Kaila. I bet you must have to be so inventive working around various allergies! I really enjoyed the experiment and might have a go at something else. I like the idea of dairy or gluten alternatives as an idea. I haven't tried dairy free milks yet in baking. My kids love non-dairy chocolate milk though. Hmmmm you've got me thinking now!