Thoroughly wash chitterlings and remove any excess fat.
Next, cut the chitterlings into small (1-2 inch) pieces and put them in a medium-sized pot, then add about 2 cups of water to cover them—Cook on high for about 1 hour.
Pour the chitterlings into a colander to drain and discard water. Rinse them thoroughly.
Rinse the pot well and place over medium heat. Add a tablespoon of cooking oil, the onion, garlic, and thyme, and saute for about a minute. Then add bell peppers and celery, and saute for another minute.
Next, add chitterlings, bay leaves, bouillon, Creole seasoning, apple cider vinegar, and 2 cups of water. Give everything a nice stir, then season with salt and pepper to taste.
Cover pot and place pot over medium-high heat. Cook for about 2-3 hours until chitterlings are tender. Keep checking the pot to make sure the water hasn't cooked out; if so, add more.
Serve with red pepper flakes or hot sauce.