1. Preheat oven to 350º F.
2. Cut the tops off the peppers and remove the seeds. Place the peppers in a large saucepan and cover with water. Bring to a simmer and cook for 3 minutes, just until the peppers are slightly soft. Drain, rinse with cool water, and set aside on paper towels.
3. Add the oil to a skillet set over medium heat. Once the oil is hot, add the onion and sauté until it turns translucent, about 5 minutes. Add the garlic and sauté for another 1-2 minutes, until the garlic is fragrant. Add the carrots and ground meat and cook, using a spoon to gently break up the meat. Stir and gently toss the ingredients together until well combined and the meat is nicely browned about 7-10 minutes.
4. Add half the pasta sauce, the seasonings, and ½ cup sour cream (if using).
5. Stir well to combine and spoon into the peppers.
6. Mix together the remaining pasta sauce and sour cream (if using).
7. Place the stuffed peppers into a deep skillet or casserole dish and top with the remaining sauce.
8. Cover with foil, place in the oven and bake for 25-30 minutes, until the peppers are soft and completely cooked.
Source: Heather Isely