Koshi-an smooth red bean paste or tsubu-an chunky red bean paste
Black sesame seeds
Melt the unsalted butter and mix with the granulated sugar.
Mix in the vanilla essence, then the eggs, mochiko, baking powder and milk in that order.
Pour the mixture into a cake tin greased with butter (not listed in ingredients) and spoon the bean paste over the top. (The bean paste will naturally sink into the batter while baking.)
Sprinkle some black sesame seeds over the top. Bake the cake in an oven preheated to 180℃ (350°F) for 40-50 minutes.
Top with whipped cream if you like.
This photo uses amanatto instead of anko for the matcha and the roasted green tea flavor.
For the matcha flavor, add 3 tablespoons of matcha powder and 2 tablespoons of milk. White sesame seeds look nice on it.
For the roasted green tea (hojicha) flavor, add 3 tablespoons of hojicha powder and 2 tablespoons of milk, also topped with the white sesame seeds.
Story Behind this Recipe
This cake recipe is often taught to Japanese housewives who have just come to America by their veteran counterparts. The recipe probably differs depending on the region.
Sweet red beans tend to sink through the batter while you're baking, so it's best to start baking with them floating on top. Looking at the colour, I think that black sesame seeds work best with this cake.