The recipe comes from Sarabeth's Bakery and they're just fantastic. Nutty, crumbly, buttery all in one. The recipe is a bit more involved than other cookies since you need to roll out the dough and cut the cookies out, but not much more. If you didn't want to cut them out with cookie cutters, you could also just cut the dough into squares or rectangles with a knife. I made tiny little sandwich cookies, so it took longer to cut them out, but you can make them however you like. The original recipe calls for hazelnuts, but I've also made them with pecans and they're delicious as well. The cookies stay crisp about a day or two after they've been filled, but will continue to soften as they sit, so don't wait too long to finish them.
Adapted from Sarabeth's Bakery
3/4 cup(3 oz) hazelnuts
2 1/2 cups pastry flour or cake flour, sifted
1 1/4 tsp ground cinnamon
1/2 tsp baking powder
1/8 tsp salt
12 tbsp. unsalted butter, room temp
1/2 cup granulated sugar
1 large egg, beaten
Raspberry preserves or ganache, for filling
In a preheated 350 deg F oven, toast the hazelnuts for 10 min and remove the skins by rubbing them together in a kitchen towel. Cool completely, then place the nuts, and 1/2 cup of the flour in a food processor. Process until finely ground.
Mix the nut-flour mixture with the remaining flour, cinnamon, baking powder, and salt in a medium bowl. Beat the butter and sugar in a mixer fitted with a paddle attachment or with a handheld mixer on medium-high speed until light and fluffy, about 5 min. Scrape down the bowl and beat in the egg.
On low speed, add in the flour mixture and mix until just incorporated. Wrap the dough in plastic wrap, flatten into a rectangle about an inch thick, and refrigerate until well chilled, at least 2 hrs.
When ready to make the cookies, working with half the dough at a time, roll the dough out on a lightly floured surface to 1/8 inch thickness. Cut cookies out with cookie cutters of your choice. Transfer cookies to a parchment lined baking sheet with an offset spatula.
Roll out and cut out cookies from the remaining dough. Gather up the dough scraps and repeat rolling and cutting out cookies. Refrigerate the dough before continuing to roll it out if it becomes difficult to work with. Refrigerate the cookies for at least 30 min to let them firm up.
Preheat your oven to 350 deg F. Bake two pans of cookies at a time, one on the top rack and one on the bottom rack, until they are lightly browned on the edges. This will take 15-17 min for larger cookies, 8-10 min for small cookies. Rotate the pans halfway through and switch from top to bottom. Let the cookies cool completely on the pan.
Sandwich the cookies with raspberry preserves or ganache. Let them sit for 8 hrs or overnight to settle and soften slightly. Store cookies in a covered container at room temp. for up to 5 days.