Line a sheet pan with parchment paper to keep clean-up simple and prevent sticking. Place broccoli in a single layer on the parchment paper. Cover with ¼ cup olive oil and toss to mix well.
Roast the broccoli in a preheated 425ºF oven for 10-15 minutes, or until the edges of the florets are slightly browned but the stalks are still bright green.
Toss the broccoli florets with shaved Parmesan cheese, reserving a few shavings for garnish. Serve Roasted Garlic Broccoli garnished with Parmesan cheese and lemon slices.