In a skillet over medium heat, brown 1 lb of lean ground beef until fully cooked, breaking it apart as it cooks. Drain any excess grease to keep your casserole light and delicious.

Add 1 chopped medium onion and 2 chopped bell peppers to the skillet. Sauté until they’re tender, about 5 minutes.

Transfer the cooked beef and sautéed veggies to your slow cooker. Stir in 1 can of drained black beans, 1 can of drained corn, 1 can of fire-roasted diced tomatoes, and 2 tbsp of taco seasoning.

Sprinkle 2 cups of shredded cheddar and Monterey Jack cheese on top of the mixture.

Cover your slow cooker and set it on low for 6-8 hours or high for 3-4 hours. Wait until the casserole is bubbly and the flavors meld together wonderfully.

Before serving, give everything a good stir to mix the layers. Ladle the cowboy casserole into bowls and enjoy!