Heat oil in a large frying pan (skillet) over a medium-high heat.
Add the chicken and cook for 5 minutes, turning occasionally, until sealed.
Add the onion to the pan (with the chicken still in there) and cook for 5 minutes, stirring often, to soften.
Add the garlic, ginger, curry powder, ground coriander, cumin, paprika, cinnamon, salt and pepper. Stir and cook for a further minute.
Add the tomato puree, tinned tomatoes, stock and coconut milk.
Bring to a gentle bubble, then simmer gently, stirring occasionally for 10 minutes – until the chicken is cooked through.
If you would like to thicken the curry, stir in the cornflour slurry. This is optional, you can leave it out if the curry thickness is to your liking.
Stir in the spinach (it should wilt quickly) then turn off the heat.
Serve with boiled rice, topped with fresh coriander and chilli flakes.
Can I make it ahead?Yes, this is a great curry to make ahead and it reheats really well. Make the curry, then quickly cool, cover and refrigerate for up to 2 days. Reheat in a pan over a medium heat (you may need to add a splash of water to loosen it up) until the chicken is piping hot throughout.Can I freeze it?Yes, make the curry, then quickly cool, and freeze it in an airtight container. Defrost in the refrigerator overnight, then reheat as per the 'make ahead' instructions above.Ingredient swaps/additions
Swap out the chicken for quorn, tofu, courgette or meatballs.
Swap out the 14oz (400ml) coconut milk for 7oz(200ml) additional chicken stock plus 7oz(200ml) double/heavy cream
Add in extra veg (see 'Want to add more veg?' near the top of this post)
Swap out the mild curry powder for medium or hot if you like it a little spicier.
How to scale up and scale down this recipeYou can halve or double this recipe, sticking to the same ratios. If you double the recipe, it will take 5-10 minutes longer to cook, and you may need to add in a little more cornstarch slurry to thicken if desired.Nutritional information is per serving, not including the serving suggestions of rice, coriander and chilli flakes.