Preheat your oven to 400°F (200°C).
In a mixing bowl, combine the olive oil, garlic powder, onion powder, paprika, dried thyme, salt, and pepper. Stir until well combined to create a marinade.
Add the chicken thighs to the bowl and coat them evenly with the marinade.
On a large sheet pan, arrange the halved baby potatoes and sliced carrots. Drizzle them with a bit more olive oil, salt, and pepper. Toss to coat.
Place the marinated chicken thighs on the sheet pan, skin-side up. Scatter the chopped bell peppers around the chicken and vegetables.
Transfer the sheet pan to the preheated oven and roast for 35-40 minutes, or until the chicken reaches an internal temperature of 165°F (75°C) and the vegetables are tender.
Once cooked, remove the sheet pan from the oven and let it rest for 5 minutes. Garnish with fresh parsley if desired before serving.