1) Put the pork in a heavy duty Ziplock bag to marinade. Add about a can and a half of coke and about 1/4 c. brown sugar. Marinade for a few hours or overnight.
2) Drain marinade and put pork. 1/2 can of coke, water, and garlic salt in a crock pot on high for about 3-4 hours (or until it shreds easily, but don't let it get too dry).Remove pork from crock pot and drain any liquid left in the pot. Shred pork.
3) In a food processor or blender, blend 1/2 can coke, chilies, enchilada sauce and remaining brown sugar (about a cup, you can add a little more or less to taste). If it looks too thick, add more coke little by little.
4) Put shredded pork and sauce in crockpot and cook on low for 2 hours. That's it.