Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.
In a mixing bowl, combine the flour, baking powder, and salt. Stir in the shredded mozzarella cheese.
Add the milk and olive oil to the dry ingredients and mix until a dough forms. If the dough is too sticky, add a little more flour.
Turn the dough out onto a floured surface and knead gently for about 1 minute. Roll the dough out to about 1/4-inch thickness.
Use a round cookie cutter or a glass to cut out circles of dough and place them on the prepared baking sheet.
Spoon a small amount of pizza sauce onto each dough circle, spreading it evenly. Top with additional mozzarella cheese and your choice of toppings.
Bake in the preheated oven for 12-15 minutes, or until the edges are golden brown and the cheese is bubbly.
Allow the mini pizzas to cool for a few minutes before serving.