Preheat oven to 350°F and grease a 9x13 baking sheet or pizza pan.
In a large mixing bowl either with a stand mixer (with the blade attachment) or hand mixer, beat the butter and sugar together on medium-speed until light and fluffy, about 2 minutes.
Add the egg and vanilla extract. Beat on medium speed until completely combined. Add in the dry ingredients and fold in all the ingredients.
Press the dough evenly into the prepared pan/dish. Use a fork to poke a few holes in the dough, to prevent it from bubbling up. Bake for 15-18 minutes, or until the dough is lightly golden. Let it cool and make the frosting.
Whisk together the frosting ingredients until combined.Spread the frosting out evenly on the baked cookie crust. Sprinkle with your favorite fruit, and drizzle with a bit of honey if desired. Slice, serve and enjoy!
Notes
You can make mini sugar cookies using the dough instead of one large pizza crust and make mini versions instead.