If any of your broccoli florets are large, cut them in half. Small ones can be kept whole.
Spread the florets on a rimmed baking sheet. Drizzle with oil, salt, and pepper and toss to evenly coat.
Roast in the preheated oven for 15 minutes. Take the baking sheet out of the oven and sprinkle the parmesan cheese on top. Roast for another 5 minutes. Scrape all of the crispy cheese from the baking sheet and serve with the roasted broccoli. Enjoy!