Preheat the oven to 170℃. Place a baking liner in the cake pan.
Combine the eggs and sugar and whip. It's easier to whip them if you use a hand mixer. It will take about 15 minutes with a whisk, 7~8 minutes with a hand mixer.
Whip until the mixture forms a thick ribbon when the whisk is lifted.
When it's very fluffy, add the pancake mix that was shaken in a plastic bag to break up flour lumps, and fold in gently.
When it's mixed in, add the soy milk and mix up from the bottom. Do the same with the olive oil and vanilla extract.
After you have mixed everything, the batter will have lost a lot of its fluffy texture, so it's important to whip really well in Step 3.
Pour the batter into the baking pan. Drop it lightly once to smooth out the surface.
Bake for about 25 minutes at 170℃ while checking from time to time. Cover with aluminum foil when it starts browning midway through.
Insert a skewer and if it comes out clean, it's done. Take out from the oven and let it cool down a little. Peel off the liner and start decorating the cake when it's cooled.
The cake made by a whisk: It became a slightly thin sponge cake that is about 4 cm high and 18 cm diameter.
You can put a lot of decorations on an 18 cm diameter cake.
The sponge was a little thin, but the end product turned out to be a perfect size for kids. It was fluffy and looked great.
For my daughter's birthday in December 2011: I used a 15 cm diameter cake and I couldn't put a lot of decorations, but it was a perfect size for a family of 4~5 people to finish up in one sitting.
Christmas cake in December, 2011: I used a large baking pan, so I doubled the amount of the ingredients. It was a big gorgeous cake and more than enough for 8 adults.
For Hinamatsuri (Girl's Day festival) in March, 2012: Using the same amount of the ingredients but with a pound cake pan. I decorated the cake first, and cut into triangles. It was a perfect size for a family of 4~5 people.
Story Behind this Recipe
I didn't have any flour, but I wanted to make a cake. I made this sponge cake a little bit healthier ingredients for my children.