Preheat oven to 350 degrees F (175 degrees C). In a large bowl break up the almond paste. Add the softened butter, sugar, eggs and almond extract. Beat batter until light and fluffy. Beat in the flour and the salt. Split the batter into thirds and add enough of the three different food colorings to each third to color the batter nicely. Spread the batters into three 9x13 and 1/4 inch deep aluminum baking pans. Be sure the batter is only about 1/8 inch thick or it will rise to high.
Bake at 350 degrees F (175 degrees C) for 12 to minutes. Cool. Remove baked and cooled cakes from pans and place on a cookie sheet or cutting board. Heat the jam and spread between the layers as you stack them. Spread the melted chocolate over the top layer and refrigerate. When stiff remove cookies from the refrigerator and let chocolate soften slightly before cutting into small rectangles.
Makes 3 dozen