1. First, fully soften the butter at room temperature, weigh the powdered sugar with an electronic scale, and mix the powdered sugar and butter first.
2. Use a manual whisk to whip the butter until the color becomes lighter and feathery.
3. Then add the egg yolk liquid several times in small amounts, and mix well with the butter until evenly, then add the next egg yolk liquid.
4. Use a tool to scrape out the orange shavings and pour it into the whipped butter.
5. Weigh the low powder and add 1/4 tsp of baking powder.
6. Sift together the low flour and baking powder and pour into the butter.
7. Weigh the almond flour and pour it into the low flour.
8. Use a spatula to fully mix the flour and butter, put the dough in a fresh-keeping bag, seal it, and send it to the refrigerator to relax for 30 minutes.
9. Take out the loosened dough, roll it into a sheet, and carve out shortbread cookies with a flower-shaped mold.
10. Point a hole in the middle of the flower-shaped shortbread with chopsticks, put it in strawberry jam, and brush the surface evenly with protein liquid.
11. Put it into the preheated oven, and bake for about 20 minutes at the upper fire at 170 degrees and the lower fire at 130 degrees. The surface can be out of the oven when the color changes.
