Grease 3 - 13 x 9 inch pans. Line with wax paper. Preheat oven to 350 degrees F (180 degrees C).
Combine almond paste, sugar, butter, egg yolks and almond extract. Beat for 5 minutes until light and fluffy. Beat in flour and salt.
In a separate bowl, beat egg whites until stiff peaks form. With a wooden spoon, fold into the almond mixture.
Divide dough into 3 -1 1/2 cup portions. Add red coloring to one of the portions, and green to the another. Spread the batter in the 3 separate prepared pans (keeping the colors separate).
Bake for 15 minutes, or until edges are golden brown. (Each layer will be 1/4 inch thick). Remove cakes from pan immediately. Cool thoroughly.
Stack layers in a 9 x 13 inch pan, spreading apricot jam between layers (no jam on top layer). Place second 9 x 13 inch pan on top and weigh down with two 5 pound bags of sugar or flour. Refrigerate overnight.
Melt chocolate over hot water and spread over cake. Allow to set. Trim edges and cup into 1 inch squares.