unsalted butter, softened
Cream butter and gradually add sugar. Beat till light. Add egg yolks and mix. Add flour and salt and mix well. Stir until dough forms a ball.
Refrigerate dough for one hour.
Fill cookie press and form the cookies on an ungreased cookie sheet. Brush on egg whites and sprinkle on colorful sugar.
Bake at 350 degrees for 10-15 minutes.
I roll the dough into balls and use a cookie stamp them sprinkle colorful sprinkles on top before baking.