1 c sliced almonds, hazelnuts, or pecans
2 c flour
1/2 tsp cinnamon
1/4 tsp salt
1 c (2 sticks) butter, room temperature
2/3 c sugar, divided
1 tsp vanilla
2 large egg yolks
Zest of 1 lemon
Powdered Sugar for dusting
1/2 cup seedless raspberry jam (or other jam of your liking)
Preheat the oven to 350 and place rack in center of oven. Toast the almonds or pecans on a baking sheet for about 8-10 minutes, or until lightly browned and fragrant. Remove from oven and place on wire rack to cool. Once the nuts have cooled, place in a food processor and process with 1/4 cup of the sugar from the recipe until finely ground. Set aside. In a separate bowl, whisk or sift together the flour, cinnamon, and salt. Set aside.
In the bowl of your electric mixer, with the paddle attachment, cream the butter and remaining sugar until light and fluffy, approximately 3 minutes. Beat in the vanilla extract, egg yolks, and lemon zest. Beat in the ground nuts. Add the flour mixture beating just until incorporated. Divide the dough in half and shape into two rectangles about 1/2 inch thick. Wrap the two rectangles of dough in plastic wrap and refrigerate until firm – at least one hour and up to several days.
Preheat oven to 350 and place rack in center of oven. Line two baking sheets with parchment paper and set aside. Remove one rectangle of dough from the refrigerator. On a lightly floured surface roll out the dough until it is about 1/4 inch thick. Using a 2 to 3 inch cookie cutter (round, square, heart, etc.) cut out the dough. Place the cookies about 1 inch apart on the prepared pan. Use a smaller cookie cutter (3/4 - 1 inch) to cut out the centers of half of the cookies on the baking sheet. (You will be sandwiching two cookies together and there will be a small 'window or cut out' in the top cookie so you can see the jam that will be underneath.)
Re-roll any scraps and cut out the cookies. Remove the other half of the dough from the refrigerator and roll and cut out the rest of the cookies. Bake the cookies for 12-14 minutes or until they are very lightly browned. Remove from oven and place on a wire rack to cool.
While the cookies are cooling place the raspberry jam in a small saucepan and heat gently until it has thickened slightly. Strain if there are any lumps in the jam. Let cool.
To Assemble Cookies: Place the cookies with the cut-outs on a wire rack and lightly dust the tops with the confectioners' (powdered or icing) sugar.
On the bottom surface of the full cookie (top of cookie will face out) spread a little (about 1/4 teaspoon) of the jam. Place the cut-out cookie on top and gently sandwich them together, making sure not to smudge the powdered sugar. Using a small spoon, fill the cut-out with a little more jam.
Makes about 15 3-inch sandwiched cookies.