Soften 1 lb of almond paste with a paddle in your mixer until broken down.
Add 1 lb confectioners sugar. Mix until no lumps and crumbly like sand.
Slowly drop in small bits of the 1 lb of all purpose shortening at a time making sure each bit is incorporated fully so as to not cause any lumps.
Once all shortening is added, mix until and scrape down the bowl, including the bottom of the bowl to ensure there are no pieces of paste left. (Don't forget or skip this step, I did last time and noticed a bunch of lumps at the bottom as I was pouring it out)
Once all the pieces of paste are gone, you may whip the mixture, still using the paddle as long as the batter doesn’t splatter all over your kitchen.
Mixture should *whip up* and actually turn whiter than when you started with it.
Once that happens and there’s enough air and it’s been whipped up nice and no lumps, add your 15 eggs, 2 tbsp of vanilla, 1 tsp of butter flavor (optional) and mix for a few minutes longer.
Add in your 1 lb of all purpose flour and once incorporated, remove from mixer. Do not over mix at this stage.
Divide evenly into 3 bowls and add whatever and how much coloring you want to your cookie. Remember it will get darker as it bakes. The more vibrant before baking, the brighter colors your cookie is going to have.
Spatula colored batter into lightly greased with parchment paper baking trays and smooth out as best as you can.
Bake at 370 for 15-17 minutes. Watch for browning on top and tap the top when you think it is finished. You don’t want them overly firm but you do want them baked all the way through. Personally, I have to bake them in shifts because the trays won't fit in my oven together.
Choose your top color and flip that tray, after they have cooled a bit, onto a parchment covered upside down baking sheet. Apply a very thin layer of the jam of your choosing and then flip the next color on top, one more thin layer of jam and flip the last color. Trim your edges and refrigerate or freeze. Up to you.
Once completely cooled, add your melted chocolate on top, cut and serve. If you want them completely surrounded with chocolate like ours from the bakery, cut them into stripes after cooling and then have your chocolate drip down the sides of the cookie as well as the tops.