Place a pizza stone in the oven (if using) and preheat to 475°F (245°C) for at least 30 minutes. If using a baking sheet, preheat the oven to 475°F (245°C).
On a lightly floured surface, stretch or roll the dough into a 12-inch round, keeping the edges slightly thicker for a crust.
Transfer the dough to a piece of parchment paper or a well-dusted pizza peel/inverted baking sheet (use cornmeal or flour to prevent sticking).
Spread the pizza sauce evenly over the dough, leaving a 1/2-inch border. Sprinkle on the mozzarella, then scatter over Italian seasoning and Parmesan.
Arrange the salami slices on top. Add the halved cherry tomatoes and red onion (if using) evenly across the pizza.
Carefully slide the pizza onto the hot stone (or place the baking sheet in the oven). Bake 12–15 minutes, until the crust is golden and the cheese is bubbling.
Remove from the oven and cool for 2 minutes. Top with fresh rucola so it lightly wilts from the heat.
Drizzle with a little olive oil and season with salt and black pepper to taste. Slice into 8 pieces and serve right away (add red pepper flakes, basil, or torn fresh mozzarella if you like).