Shredded Beef Enchiladas

Pour 1 cup water into your slow cooker. Add beef roast, then sprinkle taco seasoning and chili powder over the beef. Cover and cook on low until fall-apart tender, 8 hours. Shred with two forks. In a medium saucepan, bring enchilada sauce to a boil. Stir together cornstarch and water until dissolved in a small bowl, then add to enchilada sauce and reduce heat to medium-low, stirring until thickened. Remove from heat. Preheat oven to 350º and grease a large casserole or baking dish. Spread half of the enchilada sauce in the bottom of the dish. Arrange tortillas on a clean flat surface. Divide 1 cup cheese among tortillas. Top with shredded beef. Roll tightly and place side by side in baking dish. Top with remaining half enchilada sauce and cheese. Cover dish with foil and bake until cheese is melted, 10 to 12 minutes. Uncover and bake 4 to 5 minutes more. Top enchiladas with desired toppings and serve.