Preheat the oven to 400 degrees F. Place the sweet potato slices and red onion slices in a bowl and toss with 1/2 tablespoon of the olive oil. Season with salt and pepper. Place on a large baking sheet and bake for about 20 minutes, or until the sweet potatoes are soft and tender. Make sure you turn them once during the 20 minutes. Remove from oven and let cool while you prepare the pizza dough.

Turn the oven to 500 degrees F or as high as your oven will go. If you have a pizza stone, place the pizza stone in the oven to get hot. On a lightly floured surface, roll out the pizza dough, using a rolling pin. Roll it out to about 3/8 of an inch. Place the pizza dough on a pizza peel or pan that has been generously coated with corn meal. Lightly brush the dough with the remaining 1 tablespoon of olive oil. In a small bowl, toss the kale with balsamic vinegar. Top the pizza dough with mozzarella cheese, sweet potato slices, kale, red onion slices, and fresh rosemary.

Place the pizza in the oven-directly on the pizza stone, if using one, or on the oven rack. Bake for 10-15 minutes or until pizza crust is golden and cheese is melted. Remove from oven and let cool for a few minutes before slicing. Slice and serve warm.