• Lightly grease 7 small brioche tins. Set aside.

Make the batter:

• In a heat-proof medium bowl, combine sugar and hot water.
• Mix well to dissolve the sugar. Let cool.
• Remove 2 tablespoon of cooled sugar syrup and place into a small bowl.
• Add baking powder and baking ammonia to the small bowl of sugar syrup and stir well.
• To the medium bowl of sugar syrup, stir in vanilla extract and apple cider vinegar.
• Sift cake flour into the medium bowl of sugar syrup.
• Pour the baking powder and baking ammonia mixture into the cake flour mixture.
• Use a spatula to combine all the ingredients very well.

Color the batter:

• Prepare 3 separate bowls, each with 1 teaspoon of matcha powder, 1 teaspoon of red yeast rice powder, and 1 teaspoon of cocoa powder.
• Divide the batter into 3 equal parts, about 115g for each color and pour it into each bowl.

  Note 1: the consistency of the batter should be thick and not runny. If it appears runny, adjust and add in additional 5g of cake flour to the batter.

  Note 2: this recipe yields 7 cakes; you will have 1 extra portion -- mix in an additional 5 g cake flour to this particular plain/white portion.
• Fill the batter into greased brioche molds, to about 100% full.

Steam the cakes:

• Place the cakes into a steamer with hot water over high heat.
• Draw a cross on the surface of the batter using a toothpick/skewer.
• Cover and steam on high heat for 20-25 minutes, until puffy and the surface has cracked.