Place the pork in a crockpot with 1/3-1/2 cup water, then generously season with salt, pepper, and garlic salt. Cook on high for 4 hours or low for 8 hours--or until pork is pull-apart tender.
Preheat oven to 350 degrees, and spray your baking dish with cooking spray. Shred meat with two forks. then place in large bowl. Stir in 1 to 1 1/2 cans of the green chili sauce (if you're using 10 ounce cans, about 10-15 ounces.) Drain and rinse the black beans, then add them to the mixture along with the brown sugar. Chop the cilantro and add as much as desired. Mix until well combined.
Pour about 1/2 cup green chili enchilada sauce into the bottom of your baking dish. Down the middle of each tortilla, place the filling, then sprinkle with cheese. Roll up, then place seam side down in the baking dish. Repeat until dish is filled.
Pour the rest of the enchilada sauce on top of the burritos, then sprinkle generously with cheese. Cover the baking dish with foil, then bake for 25-30 minutes until cheese is melted and burritos are heated through. Remove the foil for the last 5 or so minutes of baking.
***Many of these ingredients are customizable to your preferences. If you want more more less black beans, enchilada sauce, brown sugar, and cheese, alter them to your liking. For example, you may only need 3-10 ounce cans of sauce if you like less.