Preheat your oven to 350°F (175°C). Line 1-2 baking sheets with parchment paper and set aside to ensure your cookies don't stick and bake evenly.

In a medium bowl, cream together the unsalted butter, salt, white sugar, and light brown sugar until the mixture is light and fluffy. Add in the egg yolk, pumpkin puree, and vanilla extract, blending well until smooth. In a separate bowl, whisk together the all-purpose flour, pumpkin pie spice, ground cinnamon, and baking powder. Gradually add the dry ingredients to the wet ingredients, mixing until a cookie dough forms. I like to make sure not to overmix at this stage for a tender cookie.

Using a spoon or a large cookie scoop, drop large balls of cookie dough onto the prepared baking sheets. Flatten each ball slightly with your hands or the bottom of a glass. You should have about 10 cookies—bake 6 per cookie sheet for best results. Bake in the preheated oven for about 13 minutes, or until the edges are lightly browned. Let the cookies cool on the baking sheet for 15 minutes, then transfer to a wire rack to cool completely before frosting.

While the cookies are cooling, beat together the softened salted butter and cream cheese in a bowl until creamy and lump-free. Add in the vanilla extract and continue beating. Gradually add powdered sugar while mixing on low speed, using at least 2 cups and adding more as needed until a thick frosting forms. If the frosting becomes too thick, add a splash of milk to thin it out—I find this tip helpful for getting a perfectly spreadable consistency.

Fill a piping bag with the cream cheese frosting (from Step 4) and trim the tip or use a 1A circular piping tip. Pipe a large swirl of icing onto each cooled cookie, starting from the center and working outward to mimic the signature Crumbl cookie look. Sprinkle the tops lightly with extra pumpkin pie spice to garnish. For a pretty presentation, I like to dust the spice directly over the frosting right before serving.