1. Preheat oven to 400°F (205°C).
2. Place sliced onions and butternut squash in a Gefen Easy Baking Parchment Paper-lined roasting pan.
3. Sprinkle with rosemary, salt, pepper, and olive oil. Toss to coat.
4. Bake 20 minutes uncovered, then set aside.
5. Raise oven temperature to 450°F (230°C).
6. Roll out your pizza dough on a floured surface. Cut out 20 circles, using either a round 3-inch (7.5-cm) cookie cutter or a glass.
7. Place your pizzettes on a parchment-paper lined cookie sheet. Add a tablespoon of butternut mixture to each round. Return to oven and bake an additional 10 minutes.
8. Serve immediately.