How to Make It
Preheat oven to 450°F with rack in lower third of the oven. In a large bowl, toss Brussels sprouts with salt, several grinds black pepper, and ¼ cup oil.
Brush a baking sheet with remaining 1 tablespoon oil. Place pizza dough onto the baking sheet and stretch until it reaches the edges.
Top dough with the mozzarella and ½ cup Pecorino all the way to the edges. Top with reserved Brussels sprouts.
Bake until dough is golden brown, 22 to 24 minutes. Top with lemon zest, remaining Pecorino, flaky salt, and crushed red pepper flakes, if desired. Cut into 35 pieces and serve warm or at room temperature.