Wash and dry broccoli well. (Dry broccoli = crispy broccoli). Trim broccoli tops off of stems and cut into equal pieces.
On a sheet pan, add broccoli heads, drizzle with olive oil, onion powder, garlic powder, lemon zest, salt and pepper. Spread broccoli mixture evenly over the whole pan leaving room between each piece. (This will allow for a crispy crust)
Roast on top rack of oven for 15 minutes.
After 15 minutes, remove from oven and toss well. Redistribute evenly back on sheet pan and grate the parmesan cheese on top of the broccoli.
Place the broccoli back in the oven and roast for another 10 minutes