500 gr flour
250 gr unsalted butter
200 gr sugar
1 large egg
1 teaspoon baking powder
1 egg white
walnuts or almonds, ground
Using an electric mixer cream the butter and sugar together until the mixture is light and fluffy (the butter should be at room temperature). Add the egg, baking powder, the flour, 1/2 cup at a time, and continue beating until the mixture becomes a slightly stiff dough.
You can add lemon rind, cinnamon, almond or vanilla flavor into the mixture.
Place the dough in the refrigerator for about 30 minutes.
Preheat oven to 325 degrees F (165 degrees C).
The difficult part is using just the right amount of flour when rolling the dough, to keep it from sticking to the pastry board or rolling pin.
Cut dough in half. Put half in the refrigerator.
On a lightly floured surface, using a floured rolling pin, roll the 1/2 of the dough into a sheet 1/8 inch thick.
Dip the cutout cookie in egg white, then in vanilla sugar-walnut/almond mixture.
Arrange them on an ungreased baking sheet or line a tray with parchment paper. Leave about and inch of space between them.
Repeat the rolling and cutting process with the other half of the dough, but before placing the second batch on the baking sheet, cut out the center of each with a small cookie cutter.
Bake in batches for 10 - 15 minutes or until light brown. Cool on cake rack for 20 minutes.
Spread tops of the solid circles/hearts with a thin coating of jam, sprinkle a cutout cookie with vanilla sugar and place on top of the one with jam, pressing the two together so they make a sandwich.
Perfect Valentine's Day dessert - Valentine's Linzer Hearts.