Heat a large non-stick skillet over medium-high heat. Add 1 lb ground beef, 1 cup diced bell peppers, and 3/4 cup diced yellow onion. Cook 5 to 7 minutes, breaking up the beef and stirring frequently, until the meat is cooked through and the vegetables are tender.

Carefully drain and discard excess fat from the skillet. Return the skillet to the stove.

Stir in 1/2 cup water and 2 tablespoons taco seasoning. Bring to a boil, then continue cooking until the water is mostly absorbed.

Add the drained diced tomatoes with green chiles (from the can listed). Cook, stirring occasionally, until any released liquid has mostly evaporated.

Sprinkle 1 cup cheddar cheese evenly over the skillet mixture. Cover with a lid and cook just until the cheese has melted.

Remove from heat, top with optional toppings (guacamole, sour cream, etc.) as desired, and serve.