Malaysian Sponge Cake

This light and fluffy cake is traditionally made with a levain, a natural pre-fermented starter, kind of like sourdough, that is used to make breads and cakes rise. Because baking without eggs can produce dense cakes, I decided to incorporate instant yeast and let it rest a long time to re-create the fluffiness—and it worked really well! At restaurants, this cake is made with evaporated milk and eggs.