Preheat oven to 375°. Line a baking sheet with foil.
In a medium bowl, toss together Brussels sprouts, 1 tablespoon oil, ¾ teaspoon salt, garlic powder, and pepper until coated. Spread onto prepared baking sheet.
Bake until Brussels sprouts are tender and lightly browned, approximately 15 minutes.
In a medium saucepan, heat remaining 1 tablespoon oil over medium-high heat. Add onion, vinegar, and remaining ¼ teaspoon salt; sauté until onion is tender, 3 to 5 minutes.
Spread 1 teaspoon Brie spread onto each bread square. Top with Brussels sprouts and sautéed onion. Serve immediately.
Notes
*We used Alouette Crème de Brie Original.
Recipe by TeaTime Magazine at https://teatimemagazine.com/roasted-brussels-sprouts-and-red-onion-bites/