Preheat oven to 450 degrees F
Begin browning beef on medium heat
Add onion and season with salt and pepper
Drain the grease!
Add the spices and mix thoroughly before adding diced bell pepper
Add tomatoes (don't forget to drain)
Simmer, covered, for 5 minutes then uncover and leave on low-medium
Add 1/2 tsp oil inside each whole pepper, and brush the insides and top with the oil, season with salt and pepper
Bake peppers, open end up, on foil lined sheet for 10 minutes
Pull peppers out and stuff each pepper to the top with taco filling
Top with cheese and bake again for ten more minutes