1. Preheat the oven to 350 degrees F. Spray a muffin top pan with cooking spray and set aside.
2. With a mixer, cream the butter and sugar together. Add the egg, lemon zest, and vanilla. Mix until well combined.
3. In a medium bowl, whisk together flour, baking soda, cream of tartar, and salt.
4. Add flour mixture to the butter mixture and mix until just combined.
5. Press about 1/4 cup of cookie dough into muffin top pan. Bake for 8-10 minutes, or until pizzas are slightly golden brown. Let the pizzas cool for 2-3 minutes in the pan. Remove to a wire cooling rack and cool completely.
6. While the cookies are cooling, make the frosting. Using a mixer, beat the cream cheese, sugars, lemon juice, and lemon zest together until smooth. Spread frosting over mini fruit pizzas.
7. Arrange fruit on each mini fruit pizza. Chill until ready to serve.
Note-if you don't have a muffin top pan, you can make a large pizza by using a pizza pan. Feel free to use your favorite fruits-kiwi, mango, raspberries, mandarin oranges, peaches, and bananas are also great toppings!