Heat the oven to 200C/180C fan/gas 6 and line a 12-hole muffin tin with paper cases. Sift the flour and bicarbonate of soda into a large bowl, then stir in the chocolate chips and sugar. Add the beaten eggs, yogurt and butter, and stir to combine. It doesn’t matter if the mixture looks a bit lumpy, it’s more important not to overmix or the muffins will turn out tough.

Fill the paper cases and bake for 20-25 mins until risen and golden brown. Transfer to a rack to cool – or eat slightly warm. Will keep in an airtight container for three days.