Special equipment: Muffin tin with paper muffin cases
Preheat the oven to 400 degrees F.
Put the flour, baking powder, baking soda, cocoa, sugar, and 3/4 cup of the chocolate chips into a large bowl. Pour all the liquid ingredients into a measuring jug. Mix the dry and wet ingredients together, remembering that a lumpy batter makes the best muffins. Spoon into the prepared muffin cases. Sprinkle the remaining 1/4 cup chocolate chips on top and then bake for 20 minutes or until the muffins are dark, risen and springy.