Mix all the crumble ingredients in a food processor then set aside. Mash your bananas in a mixer or using a hand mixer.

Mix all the wet ingredients together. then mix all the dry ingredients together, then combine together with your bananas.

Grease your pan with butter or vegetable oil shortening, and line with heatproof parchment paper. Place half of the mixture in the pan then even it out and top it with half of your crumble.

Put the remaining mixture and top it again with the rest of your crumble. Bake at 400 F for 15 minutes, then lower the temperature to 350F, and bake for another 20-30 minutes, or until the top exterior of the cake is almost firm to the touch.

NOTE: If you want to use another size of shape of fan, feel free. Just fill the pan 3/4 full, and bake until the cake is almost firm to the touch.