Line a 7 or 9 inch cake pan with parchment paper. (We have tried both)
Blitz the oats in a blender until it becomes flour.
Add in the baking powder and baking soda. Blitz, and set aside in another bowl.
In the same blender, add in the bananas, maple syrup, eggs, vanilla and apple cider vinegar.
Pour the wet ingredients out of the blender into the dry ingredients. Fold gently BY HAND until all is incorporated.
Divide the batter into two bowls. In one bowl, mix cocoa powder. Then add 2 tbsp of chocolate chips in each of the bowls.
Using one spoon for each batter to avoid contamination, alternate spoonfuls of chocolate and vanilla batter into the cake pan. [i]I like to dollop alternate spoonfuls of batter on top of each other.
If you are adding raspberries: after about ⅓ of the batter is in, gently place approximately half of the raspberries around. After you pour another ⅓, place the rest of the raspberries, reserving a few for the top.
Using a toothpick, swirl the batter.
Gently press remaining chocolate chips and few raspberries on top.
For 9 inch cake pan: bake for 25-30 mins or until brown.
For 7 inch cake pan: you need to bake for a little longer around 30-40 mins.