Season the pork with salt, pepper and 1/2 teaspoon of cumin.
In a large skillet, heat 1 tablespoon of oil over medium - high heat. Working in batches (to not overcrowd the skillet), add the pork to the skillet and cook until golden brown. Add additional oil, if needed. Transfer the seared pork to the slow cooker.
Add the tomatillos to a food processor and blend until smooth. Transfer the tomatillos to the slow cooker.
Add the onions, garlic, salsa verde, green enchilada sauce, diced green chiles, oregano, cumin and liquid smoke to the crockpot. Mix to combine.
Cook on low for 6 hours or on high for 4 hours. About an hour before serving, mix 3 tablespoons of cornstarch with 1/4 cup of water or chicken broth. Stir in the cornstarch mixture and cook for an additional hour. Adjust seasoning to taste and serve!