Step 1

Add room-temperature softened butter and powdered sugar to a large bowl, mix with a spatula until well combined.

Step 2

Beat an egg in a small bowl until the yolk and white are combined, weigh 50g egg, add the egg to the butter-sugar mixture. Mix with a spatula until well combined.

Step 3

Add all purpose flour (optionally substitute a portion of all purpose flour with almond flour and milk powder for a better taste) to the large bowl, mix with a spatula, then with your hands until well combined. (The dough should be softer and stickier than a bread dough.)

Step 4

Optionally, evenly divide the dough into two portions. Add finely chopped dried cranberries to one portion of the dough, add matcha powder to the other portion of the dough. Mix well with your hands until well combined.

Step 5

Transfer the dough on a sheet of parchment paper, shape it into a 1.5''X1.5''X10'' rectangular block (*see note 1). Keep the dough in the freezer for 30 minutes until it turns slightly hard.

Step 6

Preheat oven to 320°F/160°C.

Step 7

Take the dough out from the freezer, remove the parchment paper, and place the dough on a cutting board. Cut the dough block into ⅕ inch (½ cm) thick slices. You should be able to get about 30 slices of cookie dough.

Step 8

Place the cookie slices on a baking sheet lined with parchment paper. Optionally use a mini cookie cutter (or the larger side of a piping tip) to hollow the center of each cookie slice.

Step 9

Bake on the middle rack of the oven at 320°F/160°C for 20 to 25 minutes.

Step 10

Melt the white chocolate in a double boiler. (See Note 2)

Step 11

Wash and cut some strawberries into thin slices. Optionally cut them into heart or flower shape with a mini cookie cutter. Soak and rinse some salted sakura flowers. Pat dry the strawberries and flowers with kitchen paper.

Step 12

Fill the center of each cookie with melted white chocolate, top with a slice of strawberry, an edible sakura flower, a cashew nut, or other topping of your choice.

Step 13

Leave the cookies to cool completely on the parchment paper until the chocolate turns hard. You can keep the baking sheet in the fridge to speed up the cooling process.