Add all of the ingredients, except for the salt and pepper to the crock-pot.
Cook on high for 9 hours. At this point, the beans will be tender and a bunch of them will have popped open.
Use an immersion blender to puree the beans until smooth. Add more water as needed, or if you're feeling decadent add a couple tablespoons of butter! Season with salt and pepper to taste. Serve with shredded Mexican cheese (optional).
This recipe makes about 6 cups of beans. Some readers have not cooked the beans for the full hours and they end up with watery beans. You must cook the beans the full 9 hours, I cannot express the importance of this enough!