Preheat Your Oven: Start by preheating your oven to 220°C (200°C Fan). A high temperature is crucial for getting those lovely crispy edges. Place a large, rimmed baking tray in the oven to heat up as well.

Prepare the Sprouts: While the oven heats, prepare your Brussels sprouts. Wash them thoroughly, pat them dry, trim off the tough bottom stem, and remove any yellow or damaged outer leaves. Slice each sprout in half from top to bottom.

First Toss: In a large mixing bowl, toss the halved sprouts with the olive oil, sea salt, and black pepper. Make sure they are evenly coated.

Initial Roast: Carefully remove the hot baking tray from the oven. Spread the sprouts in a single layer on the tray, placing them cut-side down. I find that this direct contact with the hot metal gives you the best caramelisation. Roast for 15-20 minutes, or until they are tender and starting to turn golden brown and crispy on the edges.

Prepare the Topping: While the sprouts are roasting, mix the minced garlic, freshly grated Parmesan, and melted butter together in a small bowl to form a coarse paste.

Final Toss and Roast: Take the sprouts out of the oven. Drizzle the garlic-Parmesan mixture over them and toss everything together directly on the hot tray until the sprouts are evenly coated.

Second Roast: Return the tray to the oven and roast for another 5-7 minutes. Keep a close eye on them during this stage! You want the cheese to be melted and bubbly, and the garlic to be fragrant and lightly golden, not burnt.

Serve Immediately: Remove from the oven, garnish with fresh parsley if you like, and serve straight away while they are at their crispy best.