Stained Glass Cookies

Step 1
Preheat the oven to 350 degrees F (175 degrees C). Line 2 baking sheets with parchment paper and set aside.

Step 2
Beat butter and powdered sugar in the bowl of a stand mixer fitted with the paddle attachment on medium-high just until combined, about 30 seconds (mixture does not need to be light and fluffy).

Step 3
Scrape down sides and bottom of bowl and add egg yolk, vanilla extract, salt, and almond extract. Mix on low until incorporated, about 15 seconds. Scrape down sides and bottom of bowl; add half of flour. Mix on low until just incorporated, about 15 seconds. Add remaining flour and continue to mix on low until a dough starts to form, about 15 more seconds.

Step 4
Turn dough onto a clean, lightly floured work surface and form into one mass. Knead three or four times to create one smooth ball. Pat into a disc and roll to 1/4-inch thickness. Run an offset spatula under cookie dough to loosen from surface before cutting into shapes.

Step 5
Using decorative cookie cutters about 3 inches in diameter, cut out shapes of dough and transfer to baking sheets. Using a slightly smaller decorative cookie cutter (1 1/2 to 2 inches in diameter), cut out centers of cookie shapes on cookie sheets. Use a toothpick to remove dough centers if needed. Combine dough centers and other dough scraps; re-roll on a lightly floured surface and repeat cutting procedure. (After rerolling and cutting once, if desired, place any cut dough centers on a separate parchment-lined baking sheet.)

Step 6
Unwrap and place same or similar colored candies in separate zip-top bags. Use a rolling pin to roughly crush candies in bag (do not crush into a fine powder, pebble-sized pieces are okay). Fill each emptied center of cookie shapes about 2/3 full with crushed candy pieces.

Step 7
Bake on the center rack in the preheated oven until cookies have set and candy has melted, 9 to 10 minutes. (If baking cut dough centers, bake about 8 minutes.) Remove and let cool for 10 minutes on baking sheets. Repeat baking process with the remaining baking sheet. Transfer to wire racks to cool completely, about 15 minutes.