Set a rack to the highest position and preheat the oven to 425 degrees F (220 degrees C). Line a baking sheet with aluminum foil.

Place Brussels sprouts on the prepared baking sheet, cut-sides down. Drizzle with olive oil and sprinkle with garlic powder, salt, and pepper.

Roast in the preheated oven on the top shelf until golden brown, 15 to 17 minutes.

Stir together sweet chili sauce and soy sauce. Dab or brush sauce on top of Brussels sprouts and continue to roast until glaze is hot and bubbly, 5 to 7 minutes.