Whisk together the flour, baking powder, and salt (if using unsalted butter only).

Beat the butter and sugar, with an electric mixer on medium-high speed, until the mixture is light and airy.

Add the egg yolks and vanilla and beat again. This step can be done by hand too, with a whisk.

Keeping the mixer on low speed, slowly add the flour and combine well/continue mixing by hand. At this stage you could use a wooden spoon or spatula.

Once the dough comes together, use your hands to knead it to make two discs.

Wrap them in a plastic wrap and refrigerate for 30 minutes.

After 30 minutes, preheat the oven to 350oF, with the racks placed on the upper and lower thirds.

Place one disc between a floured and folded parchment paper and roll it out to ⅛ inch thickness. Put the disc, along with the parchment paper, into the refrigerator for another 30 minutes.

Meanwhile work with the other disc and return it to the refrigerator. The original recipe calls for Christmas themed cookie cutters. Fall designs have been used here and you could pick any fancy shape you like.

Cut out the main cookies to about 2-2½ inch rounds/squares/desired shapes.

Place the cookies, one inch apart, on the cookie sheets.

Using the smaller shapes (Christmas/Fall/random shapes) cut out the middles. Bake the cookies for about 8-10 minutes till they are slightly set, but still light brown. Do remember to rotate the cookie sheets midway through the baking. The cut out portions can be baked along side the bigger ones.

Remove the cookies from the oven and fill the middles with the crushed candies. Return to the oven and continue baking until the edges brown a bit and the candy is completely melted. The smaller cookies may be done by this time, if not they can be returned to the oven too.

Remove and allow the cookies to cool completely before storing them in an airtight container. Bon Appètit.