Heat some of the oil in a heavy skillet over medium high heat. Brown the pork, remove and put in a large kettle or stockpot.
Add the remaining oil to the skillet and saute the onions until soft. Add the garlic and serrano chile and cook for an additional couple of minutes. Remove and add to the pork.
Pour one of the bottles of beer into the skillet, raise the heat and deglaze the pan scraping up all the bits and pieces. Add the liquid to the pork.
Add the remaining beer, tomatillos, tomatoes, green chiles, oregano, and cumin to the stockpot. Bring the mixture to just below boiling, reduce the heat and simmer for 45 minutes.
Add the pinto beans, adjust the seasonings and simmer for an addition 30 minutes.
Heat Scale: Medium Hot
