1. Let the butter soften at room temperature, add powdered sugar and stir well.
2. Add the whole egg liquid and mix well.
3. Chop the dried black currant, put it in the egg batter, and stir well.
4. Sift in the flour and knead into a uniform dough.
5. Knead the dough into strips and freeze for one hour in the refrigerator.
6. Cut the dough into slices, put it in an oven preheated to 165 degrees, and bake for about 20 minutes.
