In medium bowl, combine flour, potato starch and salt.

Cream together butter and sugar. Add egg, brandy, lemon peel and vanilla; beat until light and fluffy.

Gradually add dry ingredients and mix until just combined. Wrap dough in plastic and refrigerate several hours.

Roll out half the dough on a lightly floured surface to 1/8 inch thick. Cut dough into 2 inch squares and place on buttered cookie sheets. Top with a tsp of Nutella. Avoid getting Nutella on edges of cookies. Refrigerate cookie sheets 15 min.

Roll out remaining dough and cut into 2 inch squares. Brush edges with water. Remove cookie sheets from refrigerator and top each square with a plain one. Press edges with fork to seal. Bake immediately in a 350 deg oven for 15 min. Or until cookies begin to brown. Cool and sprinkle with confectioner's sugar. Makes about 2 dozen.

Jam can be substituted for the Nutella (but who would want to?!)