Preheat oven to 550°F with a pizza stone on the lowest rack.
Cut 1/4" off the stem end of each Brussels sprout, then cut out the core. Discard any bruised or damaged outer leaves, then separate the remaining leaves.
Sprinkle pizza peel with cornmeal, then form dough into a pizza. Tear mozzarella into 10-12 pieces and scatter over dough. Distribute Brussels sprout leaves over the pizza. Scatter garlic and pancetta over dough as well. Sprinkle with Parmigiano and salt, then drizzle with olive oil.
Slide pizza onto hot stone. Bake 12-14 minutes; check after 7 minutes, turning 180° if baking unevenly.