Mix all of the ingredients together, except the chocolate chips, in a medium bowl - using a wooden spoon or hand whisk. Stir in half the chocolate chips.
Take two mini 16-hole muffin trays (the holes should be approx cake-pop size), and line with mini muffin liners - or spray with non-stick oil.
Divide the cake mixture between the muffins cases -approx 1 tsp of mixture for each muffin.
Top with the remaining chocolate chips and place in the oven to cook for 8-9 minutes.
Take out of the oven. If you're not using muffin liners, then it's best to take the mini muffins out of the tray as soon as possible - without burning yourself. Leave to cool, then serve on their own or topped with ice cream!