Mix the pancake mix and soy milk together with a whisk.
Divide the batter into 2 portions. Add the ground black sesame seeds to 1 portion and mix. Mix in the kinako to the other. The kinako batter will harden, so add 1 tablespoon of soy milk.
Put the sesame seed batter and the kinako batter in a mold made out of an empty milk carton as shown in the photo for the first layer.
For the second layer, alternate by putting black sesame batter on top of the kinako batter in the first layer, and kinako batter on top of the black sesame seed layer.
Move a knife or the back of a fork around in the batter following the red line in the photo. Drop the mold onto the countertop at a height to pop air bubbles.
Put 2 disposable chopsticks in the microwave.
Put the filled mold covered loosely with plastic wrap on top of the chopsticks. Microwave for 5 minutes (I did mine at 500 W).
When a bamboo skewer inserted into the middle comes out clean, it's done! (Take the plastic wrap off right away).
I received feedback that the marbling didn't go well, but the key is to just move your knife or fork around. Just do it in one go!
Story Behind this Recipe
I occasionally make cocoa and plain vanilla marbled cake, but I wondered if I could make a Japanese-flavored marbled cake, too.
In Step 6, the two disposable chopsticks under the milk carton mold prevents the cake from baking unevenly. When eating the cake, the kinako part is lighter in flavor, so you may want to start by eating that part.