In a large bowl, cream butter and sugar until light and fluffy. Beat in eggs, one at a time, beating well after each addition. Beat in extracts. Combine the flour, baking powder and salt; gradually add to creamed mixture and mix well. Stir in almonds.
Line a baking sheet with foil and grease the foil. Divide dough in half. On the foil, form dough into two 11-in X 3-in rectangles. Bake at 300 degrees for 35 minutes or until golden brown and firm to the touch. Remove from oven; increase temperature to 325 degrees.
Using the foil, lift the rectangles onto wire racks; cool completely. Place on a cutting board; cut diagonally with a serrated knife into 3/4 inch slices.
Place cut side down on ungreased baking sheets. Bake for 10 minutes on each side or until golden brown. Cool completely on wire racks. Store in an airtight container.