Preheat oven to 350 degrees. Line a 13x9x2” baking dish with parchment paper so that it runs up and over the long sides. This will enable you to pick up the cookies once they are cooked and place on a cutting board to cut cleanly.
Cream butter and sugar in a large bowl until light and fluffy.
Separate the egg and add the egg yolk and almond paste to the creamed mixture continuing to beat until well blended. Beat in flour.
Spread mixture evenly into prepared baking pan. Whisk egg white until foamy and brush over entire surface of dough.
Sprinkle sliced almonds on top of egg whites.
Bake for 35 minutes or until lightly browned.
Cool on wire rack. Lift out of pan and cut into 2” squares or 2×3” rectangles.
Store in airtight container.
ALMOND BAR COOKIES https://2cookinmamas.com/almond-bar-cookies-day-9/