Set an oven rack about 6 inches from the heat source and preheat the oven's broiler. Line a roasting pan with aluminum foil.

Spread broccolini in an even layer in the roasting pan. Sprinkle garlic over broccolini. Drizzle olive oil over the top. Season with salt and pepper.

Place under the broiler and cook, watching closely, until lightly browned and stalks are tender, 6 to 8 minutes. Serve sprinkled with Parmesan cheese.