Jules Destrooper Almond Thins

Jules Destrooper Almond Thins are very delicate biscuits based on pure butter, candy sugar and ripe soft Portuguese almonds. The company was launched in 1886 in the Belgian province of West Flanders by the founder Jules Destrooper who used almond thins as a corporate gift-item. Today, they they are shipped and sold internationally. This recipe is an attempt to reproduce these cookies.
1 cup Butter or margarine; unsalted
1 Egg
1 cup White sugar
1 3/4 cups All-purpose flour
1 teaspoon Vanilla extract
1 teaspoon Salt
2 cups Almonds; sliced
Preheat oven to 325 degrees F.
Cream the butter and sugar until light and fluffy. Add the egg and vanilla and beat until smooth.
Sift together the flour and salt and slowly add to butter mixture. Mix until just blended.
Divide batter in half and place each half on in the center of two ungreased, flat-sided cookie sheets (or SILPAT)
Dip a spatula in warm water and spread batter to cover the entire baking sheet, making sure batter is spread evenly. Sprinkle almonds and press gently into dough.
Bake each sheet about 12 minutes, or until edges are lightly browned. Remove from oven.
Cut hot cookies into neat 2-inch squares. Return to oven and bake until lightly golden... about 5 minutes. Watch carefully to prevent overbaking.
Remove from oven to a wire rack. Slide spatula under cookies to loosen. Cool completely on cookie sheets. Store in airtight containers with layers of wax paper between layers.
Makes 6 dozen