In a bowl, or your standing mixer, cream together the 110g Butter, 200g Sugar, 1 Egg, 5g Vanilla extract, and 15g Heavy cream on medium speed.
Turn off your mixer after the ingredients are creamed together. Using a spatula or spoon, scrape the walls of the bowl down to the bottom of the bowl before adding the last two ingredients.
Add 300g Einkorn flour and 1½ tsp Baking Powder to the bowl. Start mixing on low speed to avoid getting flour all over. As it becomes more incorporated into your batter you can turn the speed up to medium.
Once fully combined, turn off your mixer and scrape down the walls. If needed, mix again to fully combine ingredients. Otherwise, remove from bowl and place between two sheets of plastic wrap. Roll out, or press down, the dough and place it in the fridge for 10 minutes.
After 10 minutes, remove HALF the dough from the plastic wrap and leave the remaining half in the fridge. Roll out the dough to ¼-inch thickness.
Cut out cookies and place them on trays. Put them back in the fridge while you start to preheat the oven to 375℉. Once the oven is preheated, remove the trays from the fridge and place them in the oven for 8-10 minutes.