An Asian sponge cake recipe that makes very, very moist, light-as-air and fluffy banana cupcakes. This recipe uses healthier, plant-based oil, instead of butter. (Source: Baking Code by Chef Alex Goh).
Pre-heat oven to 180 deg C (350 deg F). Arrange 12 -15 (or more, if required) paper cups on a large baking tray, or lightly grease an 8-inch (20-cm) cake pan.
In a large bowl, combine flour, baking powder and baking soda and stir together until well mixed. Set aside. Mash bananas with salt, set aside.
In a mixer bowl, using an electric or hand-held mixer with a whisk attachment, whisk eggs and sugar at high speed (speed 4 on my Kitchen Aid mixer) until pale and thick, about 3 to 4 minutes.
Add mashed bananas to the whipped egg mixture, and whisk at high speed for 15 to 20 seconds until well incorporated.
Add milk, whisk for 10 seconds or until well incorporated. Add flour mixture and whisk at medium speed (speed 3 on my Kitchen Aid mixer) until just well combined.
Add in oil, and fold into the batter until well combined. Fold in the raisins, using light and gentle moves, until well distributed throughout the batter.
Scoop out batter into paper cups arranged on a baking tray (or pour batter into greased cake pan), and sprinkle chopped walnuts on top. Place baking tray or cake pan in the centre of the oven. Bake for 25 to 30 minutes, or until a metal or bamboo skewer inserted into the centre of the cupcakes (or cake) emerges free of sticky batter.