Pre-heat the oven to 180°C (fan)/200°C/gas mark 6. Place 12 muffin cases* in a non-stick muffin tin.
If using a flax egg to make these muffins vegan then mix 1 tbsp ground flax seed with 2 tbsp cold water and set aside to thicken.
Mix 175g self raising flour, 1 tsp baking powder and 125g light brown sugar together in a large bowl. Use a fork or your fingertips to separate the sugar if it's a bit lumpy.
Beat the egg (if using), then add to 60g melted butter, dairy free spread or coconut oil and 120ml milk.
Fold the flour and sugar mixture into the wet ingredients. Finally gently mix in 125g redcurrants (see note above about drying them).
Spoon the mixture into the muffin cases, filling each one halfway. Sprinkle a little sugar over the top (optional) and bake for 20 minutes in the pre-heated oven until well risen and firm to the touch.