In a large bowl, whisk to combine the flour, baking powder, and salt. Set aside.
In another bowl use a hand mixer to cream together the butter and sugar for one minute until combined and fluffy, then mix in the egg and vanilla extract.
Add the dry ingredients to the wet, and mix this on low speed until a crumbly dough forms. Dump the dough out onto a countertop and shape the dough into a flat smooth disk. Wrap it in plastic wrap, then chill in the fridge for at least one hour*, so the crust doesn’t spread out too much when baking.
Preheat the oven to 350 degrees F.
Unwrap the cookie dough, then roll it out into about a 12” circle, and set on a silicone mat or parchment paper. Bake for about 18 minutes until slightly golden on the edges, then let cool.
While the cookie crust cools, whip together the cream cheese and marshmallow cream for two minutes on high speed, until fluffy and combined.
Frost the pizza crust with the frosting, then add the sliced fruit in rows on top. Slice and enjoy!
*Really, make sure you refrigerate it. I tested out skipping this step, and the crust spreads out too much and bakes unevenly.