Preheat oven to 425 degrees F. In a large bowl add bell peppers, potatoes, onion, garlic, olive oil, Italian seasoning, salt and pepper. Stir well with a large spoon, transfer onto large 9x13 rimmed baking sheet and spread into a single layer.
In a same bowl, add chicken breasts, olive oil, garlic, Italian seasoning, salt and pepper. Using tongs, stir well to coat and place on top of vegetables.
Roast chicken and veggies for 35 minutes or until potatoes are tender.
Remove from the oven and serve warm.
Notes
Store: Refrigerate leftovers in an airtight container for up to 5 days. I do not recommend to freeze leftovers because bell peppers will turn mushy and potatoes will brown.