Place a 12-inch cast-iron skillet in the oven and preheat to 500 degrees F.
Meanwhile, roll or stretch the dough into a 14-inch circle. Carefully remove the skillet from the oven. Drizzle two thirds of the olive oil into the skillet, then carefully transfer the dough to the skillet, pressing the dough up the edges. Spread the sauce over the dough, making sure to get all the way to the edges. Shingle the pepperoni over the sauce and top with the mozzarella pearls. Brush the exposed dough with the remaining olive oil. Bake on the bottom rack until golden brown, 12 to 14 minutes.
Transfer to a cutting board, top with torn basil, cut into slices and serve.