Preheat oven to 425 degrees F.
Add the cauliflower florets to a large bowl. Drizzle the olive oil over the florets and stir to coat.
Add the lemon zest, kosher salt, pepper, and grated Parmesan cheese to the bowl. Stir until all of the cauliflower florets are equally coated.
Transfer the cauliflower to a baking pan. Bake for 30-35 minutes, or until the cauliflower is a deep golden brown and the cheese is slightly charred. Season with salt and pepper to taste. Squeeze the lemon juice over the hot cauliflower. Serve immediately.