Chocolate Sponge

This chocolate sponge can be eaten as it is but also used as a bottom sponge of many types of cakes. Therefore, I bake this sponge like a sheet and hollow out for other use. You can freeze to store. As other sweets, this is also gluten free by using rice powder instead of wheat flour.

Ingredients
Egg yolk　　　　　　70g
Sugar for egg yolk　　35g
Rice powder　　　　　15g
Corn starch　　　　　15g
Cocoa powder　　　　15g
Butter　　　　　　　35g
Egg white　　　　　70g
Sugar for egg white　35g

How to cook
1. Place oven paper on oven-pan. Sift rice powder, corn starch, and cocoa powder together.
2. Beat egg white and add sugar 3 times, 10g each. Make a firm meringue.
3. In a separate bowl, beat egg yolk and sugar thoroughly.
4. Mix egg white and egg yolk.
5. Add rice powder, corn starch, and cocoa powder.
6. Add melted butter and mix well.
7. Pour into oven-pan. Cook for 12 minutes at 180C.
8. Hollow out and freeze to store.

*If egg whites are remained, freeze to store. You can use frozen egg whites to make macarons.