Heat a large, heavy-bottomed, non-reactive pot on medium-high heat, no oil necessary. I suggest using an enamel covered cast iron pot such as a Le Creuset dutch oven.
Cook 2 pounds of ground beef & 2 pounds of ground venison until well done and browned, breaking up the chunks of meat with a wooden spoon every couple of minutes. All the liquid in the pot will evaporate and then the meat will start to brown.
Add the 3 cups of diced onion and 1 tablespoon of garlic and sauté until translucent, covered with a lid, about 10 minutes. Next mix in 1 tablespoon chili powder, 2 tablespoons smoked paprika, 2 tablespoons onion powder, 1 tablespoon garlic powder, ½ teaspoon cumin, and 2 tablespoons finely chopped chipotle in adobo. Season with 1 tablespoon sea salt and freshly cracked black pepper to taste.
Add the 3 cans of tomatoes, and 2 cups of beef stock. Return the lid to the pot, and cook for 1 hour on low heat, stirring frequently. Check for seasoning.
Ladle into soup bowls, then garnish with the divided sour cream, shredded cheese and green onions, if desired.
The chili will hold in the refrigerator for up to a week, but make sure to cool it down properly. Fill a large container with ice water and place the uncovered container of chili in the ice water until it’s chilled. Then refrigerate.