1In a large mixing bowl, beat the butter with an electric mixer on medium-high speed for 30 seconds.
2Add the brown sugar, baking powder, lemon peel, cinnamon, all spice, and salt and beat till combined.
3Beat in the egg yolks and vanilla.
4Beat in any remaining flour and ground walnuts with a wooden spoon.
5Divide dough in half. Cover and chill for 1 hour or till dough is easy to handle.
6. On a lightly floured surface, roll each half of dough to a 1/8” thickness. Using a cookie cutter, cut out dough. Place 1” apart on ungreased baking sheets. Using a small cutter, cut out the centers of half the unbaked cookies. Remove the centers and reroll dough.
7Bake cookies in a preheated 375* oven for 7-9 minutes, or until edges are firm and bottoms are browned. Remove cookies with a spatula and cool on a rack.
8To assemble cookie sandwiches sift confectioners’ sugar over the tops of the cookies with cutouts in center. Set aside. Spread about ½ tsp. of the jam onto the bottom of each cookie without the cutout; top with a cutout cookie, confectioners’ sugar side up.