Lemon sandwich cookies

Ingredients

• 3/4 cup butter, softened
• 1/2 cup sugar
• 1 egg yolk
• 1/2 teaspoon vanilla extract
• 2 cups all-purpose flour
• 1/4 cup finely chopped walnuts
• FILLING:
• 3 tablespoons butter, softened
• 4-1/2 teaspoons lemon juice
• 3/4 teaspoon grated orange peel
• 1-1/2 cups confectioners' sugar
• 2 drops yellow food coloring, optional
• Directions

1. In a large bowl, cream butter and sugar until light and fluffy. Beat in the egg yolk and vanilla. Gradually add flour and mix well.
2. Shape into two 14-in. rolls; reshape each roll into a 14-in. x 1-1/8-in. x 1-1/8-in. block. Wrap each in plastic wrap. Refrigerate overnight.
3. Unwrap and cut into 1/4-in. slices. Place 2 in. apart on ungreased baking sheets. Sprinkle half of the cookies with nuts, gently pressing into dough.
4. Bake at 400° for 8-10 minutes or until golden brown around the edges. Remove to wire racks to cool.
5. In a small bowl, cream the butter, lemon juice and orange peel until fluffy. Gradually add confectioners' sugar until smooth. Tint yellow if desired. Spread about 1 teaspoon on bottoms of the plain cookies; place nut topped cookies over filling. Yield: about 4-1/2 dozen.