Preheat your oven to 400°F (200°C). Line a large baking sheet with parchment paper for easy cleanup.
Prepare the cauliflower: Remove the outer leaves from the head of cauliflower. Place the cauliflower stem-side down on a cutting board. Using a large, sharp knife, carefully slice the head into two thick, 1.5 to 2-inch 'steaks' from the center. The florets on the sides may crumble away; you can save these to roast alongside the steaks.
Season the steaks: In a small bowl, mix together the garlic powder and Italian seasoning. Gently brush both sides of each cauliflower steak with olive oil. Sprinkle evenly with the seasoning mix, salt, and pepper.
Roast the cauliflower: Carefully place the seasoned steaks on the prepared baking sheet. Roast for 15 minutes. Gently flip the steaks and roast for another 10 minutes, or until tender and golden brown at the edges.
Add the cheese: Remove the baking sheet from the oven. Generously top each steak with the shredded mozzarella cheese. Return to the oven and bake for another 5-7 minutes, or until the cheese is completely melted and bubbly. For extra browning, you can switch the oven to broil for the last 1-2 minutes, watching carefully to prevent burning.
Serve immediately, garnished with fresh parsley if desired.
Notes
Chef's Tip: To ensure the steaks hold together, make sure to cut them from the very center of the cauliflower head where the core is thickest.Variations: Feel free to add a pinch of red pepper flakes for some heat, or sprinkle with smoked paprika for a smoky flavor.Storage: Store leftover cauliflower steaks in an airtight container in the refrigerator for up to 3 days. Reheat in the oven or an air fryer to maintain crispness.