Ingredients 1/2 cup butter, softened 1/2 cup granulated sugar 1 tablespoon poppy seed 1/8 teaspoon baking soda 1 egg yolk 1 tablespoon milk 2 teaspoons finely shredded lemon peel 1/2 teaspoon vanilla 1 1/2 cups all-purpose flour 1 cup sifted powdered sugar Directions Beat butter until fluffy, about 30 seconds on medium if using an electric mixer. Add the sugar,…