Grind butter and icing sugar with a help of table spoon until smooth and homogeneous.
Add egg and bring the mixture to a homogeneous state again.
At last add sifted flour mixed well with salt.
Knead a smooth and homogeneous dough, then wrap it in plastic wrap, and place it in the refrigerator overnight.
Lay out a sheet of parchment paper. Roll out the dough on the parchment to a thickness of 3 mm. Use a rolling pin or cookie cutters to create a design on the dough. Then, use cookie cutters to cut out the shapes. Trim off any excess dough and knead it with the remaining dough until smooth. Repeat the process.
Bake cookies for 8-9 minutes until the edges are browned. Please refer to your oven’s specifications to adjust the baking time correctly.