Start by preparing the veggies for broiling by laying them out on a cookie sheet lined with aluminum foil, and get your skillet on high heat. I put the tomatillos, pepper, and serrano chile’s skin side up, and put the tomatoes flesh side up. Drizzle or spray the veggies with a little bit of olive oil, and season with salt and pepper. Put tray under the broiler, and cook until you get a good char on the veggies.
While the veggies are charring, make sure your skillet is hot, and season the pork butt with salt and pepper. Sear the pork butt on all sides until you’ve got nice browning. Once the veggies are charred, and the pork butt is nicely seared, place them in the Crock Pot. The veggies will have given up some of their juices in the pan, so make sure to get those precious juices in the Crock Pot too.
While your skillet is still hot, pour in one cup of the chicken stock, and using a wooden spoon, get all the pork bits off the bottom of the pan. Pour this liquid, along with 1 more cup of chicken stock into the Crock Pot. You can cook this on high for 4 hours, or low for 8 hours.
Once it’s finished cooking, remove the pork from the pot, and set aside. Take the liquid and veggies and blend together with a blender or immersion blender, and pour back into the Crock Pot. Once the pork cools, pull it apart into bite size chunks and return that to the Crock Pot. Mix together and serve alone, top it with a sunnyside-up egg for a nice breakfast, or serve along side beans, rice, and tortillas for a hearty dinner.