Place chicken breasts in slow cooker and sprinkle 2 Tbsp of the taco seasoning over the top. Cook on low for 4 hours or until chicken is tender and shreds easily. Shred chicken and stir in the remaining taco seasoning and ¼ C of water. Return cover and cook an additional 10 minutes.
Spread ½ C of enchilada sauce into the bottom of a 9x13" pan.
Heat tortillas until pliable and place about ¼ C of the chicken in the middle of each tortilla with about 2 Tbsp of the cheese. Roll and arrange in the 9x13" pan. Repeat until all the chicken and tortillas are used.
Pour remaining enchilada sauce over the top of the enchiladas and top with remaining cheese. Cover pan with foil and bake @ 375 degrees for 20 minutes, remove foil and bake an additional 10-15 minutes or until enchilada sauce is bubbling and cheese is well melted.