Combine butter and sugar in a large bowl; beat at medium speed with an electric mixer until light and fluffy. Add eggs, beating well. Mix in liqueur.
Combine flour and next 3 ingredients; add to butter mixture, beating well. Stir in almonds.
Divide dough in half; shape each portion into a 9- x 2-inch log on a greased baking sheet.
Bake at 350° for 30 minutes or until firm. Cool on baking sheet 5 minutes. Remove to wire racks to cool completely.
Cut each log diagonally into 1/2-inch-thick slices with a serrated knife using a gentle sawing motion. Place on ungreased baking sheets.
Bake at 350° for 5 to 7 minutes. Turn cookies over, and bake 5 to 7 additional minutes. Remove to wire racks to cool.
*1 1/2 tablespoons chocolate syrup may be substituted.