In a large bowl, cream the butter, almond paste and 2 cups sugar until light and fluffy. Beat in eggs and extract. Gradually add flour just until moistened.
Spread into a greased 13x9-in. baking dish. Sprinkle with remaining sugar; top with almonds.
Bake at 350° for 30-35 minutes or until a toothpick inserted in the center comes out clean. Cool on a wire rack. Cut into squares. Store in the refrigerator.