Sift 100g self raising flour, 60g rye flour, 40g cocoa powder, 1 tsp baking powder and 1/2 tsp bicarbonate of soda together. Add any bran left in the sieve to the bowl and stir in. Set aside.
Place 50ml vegetable oil, 100ml honey or maple syrup and 1 egg (or flax egg*) into a mixing bowl. I use a stand mixer but you can do this with a handheld mixer or by hand with a wooden spoon. Beat well for 2 minutes.
One by one add one grated courgette, 1 ripe mashed banana and 60ml milk, beating a little after each addition.
*To make a flax or chia egg mix together 1 tbsp ground flax or chia seeds with 2-3 tbsp cold water. Set aside and allow to thicken for a few minutes.