Make the Sugar Cookie Pizza
1-Preheat the oven to 350ºF (177ºC) and: Preheat the oven to 350ºF (177ºC) and use baking spray to coat the bottom and sides of a 12 inch round pizza pan or 9×13 inch sheet pan.
2-In a medium bowl, add the flour,: In a medium bowl, add the flour, baking powder, baking soda, and salt. Whisk together and set aside.
3-In the bowl of your stand mixer: In the bowl of your stand mixer fitted with the paddle attachment (or with a large bowl and hand mixer) cream together the butter and sugar on high speed until pale and fluffy, 2-3 minutes.
4-Turn the mixer to medium and add: Turn the mixer to medium and add the egg, egg yolk, and vanilla. Mix until combined, then add the flour mixture and mix on low speed until a uniform cookie dough forms.
5-Press the cookie dough into the prepared: Press the cookie dough into the prepared pan in an even layer, all the way to the edges. Bake for 12-14 minutes, until the edges are just starting to brown (I took mine out at 13 minutes). It will continue baking as you cool it in the pan.

Make the Cream Cheese Frosting
6-In the bowl of your stand mixer: In the bowl of your stand mixer fitted with the paddle attachment (or with a large bowl and hand mixer), beat together the cream cheese and butter on high speed until fluffy and smooth, about 4 minutes. Add the powdered sugar, vanilla, and salt. Mix on low speed until combined and uniform, scraping down the bowl and paddle as needed.

Assembly
7-Once the sugar cookie pizza is cooled,: Once the sugar cookie pizza is cooled, add all of the cream cheese frosting on top and use an angled spatula to smooth it down until it reaches about 1/4 inch from the edges. Arrange the berries on top, then serve!