Fresh garlic and rosemary infuse the bread with its intoxicating flavors and aromas.
Preheat oven to 425 degrees. In a small saucepan, heat butter and oil over medium heat. Add garlic and salt; cook, stirring, until garlic is fragrant but not browned, about 1 minute. Remove from heat; set aside.
Sprinkle the bottom of two rimmed baking sheets with cornmeal. Divide the dough into four equal pieces. Roll out each piece into a 1/4-inch-thick round. Arrange two rounds on each sheet. Brush with butter mixture, leaving most of the garlic behind. Sprinkle rounds with chopped rosemary; arrange a few small sprigs on top of each.
Bake flatbreads until golden brown, about 15 minutes. Transfer to a wire rack to cool slightly. Drizzle with oil, and season with salt. Serve warm or at room temperature.
Premade pizza dough, either refrigerated or frozen, can be purchased at your local pizza parlor or grocery store.