Brown beef in a large skillet until no longer pink, stirring occasionally to break up chunks. Add chili powder, cumin, garlic powder, onion powder, salt, paprika, oregano, pepper, and 1 cup water. Stir well and bring to a simmer. Simmer 20 minutes.
While beef is cooking, cut peppers in half lengthwise and remove seeds and membranes. Remove stems if desired. (I didn’t.) Arrange peppers cut sides up on an oven safe dish. (A cast iron skillet or baking sheet works great.) Grate cheese. Cut lettuce into ribbons. Chop cilantro. Preheat oven to 350.
When taco meat is done, scoop meat over peppers. Top with cheese. Bake at 350 10 minutes or until cheese is melted. Remove from oven and top with lettuce, tomatoes, and optional toppings.
Hint: make double the seasoned meat and freeze for an easy night of nachos in your future!