Preheat oven to 425°F (220°C) and place a baking sheet inside to heat up.
Trim the ends of the Brussels sprouts and remove any damaged outer leaves.
Halve each sprout lengthwise for even cooking.
Dry them well with a towel—moisture prevents crispiness.
In a large bowl, toss sprouts with olive oil, salt, and pepper.
Spread them cut-side down on the hot baking sheet.
Roast for 20–25 minutes, shaking or flipping halfway through.
When golden and crispy, remove from oven.
Toss with minced garlic, Parmesan, or balsamic glaze, if desired.