Preheat the oven to 200C/gas 6/ fan 180C and very lightly butter a 12-hole muffin tin. Sift the flour and baking powder into a bowl. In another bowl, lightly beat the eggs, then stir in the melted butter, milk and blueberrys. Add to the flour with the remaining ingredients. Combine quickly without overworking (it’s fine if there are some lumps left – you want it gloopy rather than fluid). Spoon the mixture into the muffin tin. Bake for 20-25 minutes until well risen and pale golden on top.
Leave in the tin for a few minutes before turning out. When cool, they’ll keep in an airtight tin for two/four days. (Can also be frozen for up to 1 month.)