Step 1

Bring 2 cups water and butter to a boil in a saucepan; add rice and seasoning packet. Return to a boil, cover saucepan, reduce heat to low, and simmer until most water is absorbed, 20 to 25 minutes. Fluff rice using a fork.

Step 2

Spray a 9x13-inch baking dish with cooking spray.

Step 3

Bring a pot of water to a boil; cook poblano peppers until slightly tender, about 5 minutes. Transfer peppers to a bowl of ice water to stop the cooking process; drain. Pat peppers dry and place in the prepared baking dish.

Step 4

Heat a large skillet over medium-high heat. Cook and stir beef in the hot skillet until browned and crumbly, 5 to 7 minutes; drain and discard grease. Season beef with black pepper. Mix 1/2 cup water, chili powder, cumin, onion powder, garlic powder, and cayenne pepper into ground beef; cook and stir until liquid evaporates, 2 to 3 minutes.

Step 5

Preheat oven to 350 degrees F (175 degrees C).

Step 6

Mix rice into beef mixture; cook and stir until evenly mixed and all liquid is evaporated, 5 to 10 minutes. Spoon mixture into the peppers.

Step 7

Stir tomato soup and about 1 tablespoon water together in a bowl until soup is thinned to a gravy consistency, adding more water if needed. Pour tomato gravy over stuffed peppers; top with mozzarella cheese. Cover baking dish with aluminum foil.

Step 8

Bake in the preheated oven for 20 minutes. Remove aluminum foil and continue baking until cheese is slightly browned, 10 to 15 minutes more.