add 1 tablespoon of olive oil to a very large pot on medium-high heat. Next, add in the onions and garlic and caramelize. Once the onions and garlic are brown, add in the peppers and cook for 10 minutes on high heat.
Add onions & peppers into the slow cooker.
Add all other ingredients except the chocolate. Thicken with tomato paste if need be.
Slow cook 4 hours on high or 8 hours on low. (less time could be done. You just want all the flavors to meld together)
-Stir in chocolate once slow cooker is turned off. Serve.