Preheat the oven to 480F (250C).

Mix cake flour and baking powder in a bowl. In a second bowl, put baking soda in milk and stir.

In a large bowl, mix butter and sugar with a wooden spatula. Add Miso Paste and egg and mix until smooth. Add the milk mixture and mix well. Add the flour mixture and mix further, but do not over mix. Let the batter sit for 30 minutes.

Put batter in a piping bag, and pipe 3" (7cm) rounds on a baking sheet with parchment paper. Slash a cross in the middle of the top of each round with an oiled knife.

Bake in the oven for 8-10 minutes.