Preheat your oven to 425°F (220°C). Position the oven racks in the middle.

Chop the sweet potatoes, carrots, red bell pepper, and red onion into uniform 1-inch pieces.

In a large mixing bowl, combine the chopped vegetables with olive oil, minced garlic, rosemary, salt, and black pepper. Toss until coated.

Spread the seasoned veggies in a single layer on a rimmed baking sheet.

Roast the veggies for 25-30 minutes, flipping them halfway through for even caramelization.

Once roasted, let cool slightly and garnish with additional rosemary and flaky sea salt before serving.