put the diced pork in a sauce pan,pour in water to cover,bring to a boil,lower the heat and simmer for 40 minute.
meanwhile,soak the dried chile in hot water for 30 min until softened,drain,remove the stem and seeds.chop it.
drain the pork and shred it,set it aside.
heat the oil in a pan and saute the garlic and onion for 3 min until translucent,add the chopped chile and tomatillos,cook,stir constantly until the tomatillos start breaking up.lower the heat and simmer the sauce for 10 min,cool slightly and puree it in a blender.
preheat oven to 350F,microwave the corn tortillas wrapped in wet paper towel for 30 sec.spoon one-sixth shredded pork onto the center of each tortilla and roll it up,put them in a baking dish,face-side down,completely cover the enchiladas with the sauce,sprinkle cheese on top,bake for 25-30 min or until cheese bubbles.