Add beans to water and bring to a boil, then partially cover and bring to a simmer.
Chop the Onion, Garlic, and Bacon and add into the pot. Add the rest of the ingredients except Salt, Bacon grease and Cheese.
Simmer for 2 hours adding water if necessary to keep beans covered.
After the 2 hours add the Salt and Bacon grease. Correct seasoning with more cumin, oregano, and cilantro (don't add more salt yet). Simmer 30 more minutes.
Taste again and correct seasoning, this time you can add more salt, if desired.
Drain beans reserving 1 cup of cooking liquid. Put beans back into pot and mash with a potato masher or 'boat motor', adding the cooking liquid until you have desired consistency. Mix in the cheese and serve immediately.Garnish with more cheese and fresh cilantro if desired.