1 cup unsalted butter, softened
1/2 cup sugar
1-1/2 T grated lemon peel
1 egg yolk
1 tsp lemon extract
1/4 tsp salt
2-1/2 cups flour

Preheat oven to 375 degrees. Cream butter; gradually add sugar and beat until fluffy. Beat in lemon peel, egg yolk, lemon extract and salt. Add flour and stir just until blended. Roll into balls. Place 3" apart on an ungreased baking sheet. Dip bottom of a glass into sugar. Press down onto dough, flattening into 1/4" thick rounds. Bake until edges begin to brown, about 10 minutes. Transfer cookies to racks and cool. Sift powdered sugar over tops.