unsalted butter, room temperature • (1.4 oz, 4.5 Tbsp) powdered sugar • beaten egg, room temperature • (2.7 oz, 3/5 us cup) cake flour, or all-purpose flour • Matcha powder • ground almonds • vanilla oil, optional • (1 - 1.5 tsp) Matcha powder • (1.6 oz, 5 Tbsp) powdered sugar • or a little more milk