Preheat the oven to 220C/450F/Gas 7. Line a nine-hole mini-muffin tray with muffin cases.
Beat the egg in a bowl, then stir in the grated courgette, grated carrot, raisins, milk and sunflower oil.
In a separate bowl, mix together the flour, sugar and baking powder.
Gradually stir the wet mixture into the dry mixture until sticky and well combined.
Divide the cake mixture among the muffins cases in the muffin tray. Bake in the oven for 12–15 minutes, or until a skewer inserted into the centre of the muffins comes out clean. Remove each muffin from the tray and set aside to cool on a wire rack.