Brown the Beef. In a large skillet over medium-high heat, brown the ground beef, breaking it up with a spoon as it cooks. Drain off any excess grease.
Season the Beef. Stir in the taco seasoning and water. Bring to a simmer and cook for 5 minutes, or until the liquid has reduced.
Add Beans and Tomatoes. Stir in the black beans and diced tomatoes and green chiles. Cook for another 3-5 minutes, stirring occasionally, until everything is heated through.
Warm the Tortillas. Warm the tortillas in a dry skillet, microwave, or oven.
Assemble the Burritos. Lay a warm tortilla on a flat surface. Sprinkle cheese, beef mixture, and more cheese.
Roll the Burritos. Fold in the sides of the tortilla, then fold up the bottom over the filling and roll tightly to enclose.
Melt the Cheese (Optional). Grill in a skillet or bake in a preheated oven until the cheese is melted and gooey.