In a medium-size skillet saute the onion in a couple of drizzles of olive oil for 2 minutes or until softened.. Add garlic and saute for 1 minute longer. Add Italian sausage to the pan, cook until no pink remains. Drain any excess fat from the pan. Set aside.
To assemble: Preheat the oven to 425°F. On a silpat or parchment paper, stretch the dough into roughly a 13 x 10 inch rectangle.
Sprinkle with half of the shredded mozzarella cheese.
Arrange the cooked sausage on top, then drizzle with the pizza sauce.
Top with the remaining shredded cheese. Begin to roll starting from the widest edge. Arrange seam side down on the prepared baking sheet.
Brush the top and sides with melted butter, then sprinkle with Italian seasoning onion powder and garlic salt. Finish with Parmesan cheese.
Bake for 18-20 minutes or until golden and cooked through. Rest for 5 minutes before cutting into 1 inch slices.
Serve with additional pizza sauce for dipping, if desired.