Preheat the oven to 400°F.
Trim the stem ends from the Brussels sprouts.
Remove any yellow, damaged, or loose outer leaves.
If the Brussels sprouts are large, cut them in half to ensure even roasting.
Place the prepared Brussels sprouts in a large mixing bowl.
Add the olive oil, chopped garlic, kosher salt, and freshly ground black pepper.
Toss until the Brussels sprouts are evenly coated with the oil and seasonings.
Transfer the Brussels sprouts to a rimmed baking sheet.
Spread them into a single even layer, leaving space between the pieces when possible.
Roast for 30 to 35 minutes, stirring occasionally, until the Brussels sprouts are tender and deep golden brown.
Remove the baking sheet from the oven.
Taste and sprinkle with additional kosher salt, if desired.
Serve warm.