Microwave Gluten-Free Fluffy Sponge Cake

Generously butter the inside of a large, microwave-safe cereal bowl. Whisk eggs, sugar, baking powder, quinoa flour, sorghum flour, millet flour, olive oil, peanut butter, butter, cinnamon, and vanilla extract together in the bowl until flour is evenly mixed into the batter.

Cook in microwave until cake is cooked through, 1 1/2 to 2 minutes.