Make the cookie dough the day before. To break up this recipe, I highly recommend making the cookie dough the day before and letting it chill overnight. If you'd rather make these all in one day, they can be baked the same day so long as the dough has at least one hour to chill in the fridge.
Freeze the cutout cookie dough. To ensure the cutout cookies hold their shape, freeze them for about 15 minutes before baking.
Prepare the ganache ahead of time. The ganache will need about 1 hour to cool & set up to the right consistency, so plan ahead and account for that time!
Pair up the cookies before assembling. Once you're ready to assemble, match the top cookies with bottom cookies. Then, separate them and sprinkle powdered sugar on the top cookies, and spoon the ganache on the bottom cookies. Sandwich them together for perfectly aligned cookies!