Preheat oven to 400°F.
Trim leaves from the base of the cauliflower.
Combine butter, garlic, lemon zest, salt, and pepper. Brush mixture over the entire cauliflower head.
Place cauliflower in a large Dutch oven*, cover, and bake for 40 minutes or until tender.
Uncover, sprinkle on parmesan cheese and bake for 10-15 minutes more, until the cheese is browned and crispy. Garnish with parsley, if desired.
