Preheat oven to 400°F. Lightly oil a large baking dish or sheet pan.
Add potatoes, onion, and tomatoes to the pan. Drizzle with olive oil and season with garlic powder, oregano, thyme, salt, and pepper. Toss well.
Arrange sausage links on top of the vegetables.
Roast uncovered for 40–45 minutes, turning sausages halfway through, until golden brown and potatoes are tender.
Garnish with fresh herbs before serving, if desired.
