Optional but tasty:
Bring roast to room temperature. Heat 2 to 4 tbs oil in a large skillet over medium-high heat. Sear each side of the venison until browned, then transfer to the slow cooker. Reduce the heat to low, then pour in the stock to deglaze the pan. Add that liquid to the slow cooker.
Add all remaining ingredients to the slow cooker, then cover and cook on low until the meat is fork tender. On low, it’ll take about 5 to 7 hours. High could work as quickly as 2 hours, but may not turn out as tender if the animal was a bit older.
Serve with an array of cotijo, cilantro, salsa, tortillas, lime, and anything else you’d enjoy!