Cut steak into cubes or fine strips.

Place steak in a skillet with about 1/4 cup water; salt and pepper, then cover.

Let simmer until steak is cooked through.

Preheat oven to 300°F (150°C).

Cut tops off green bell peppers and remove seeds and membranes to clean out each pepper.

Place some mozzarella cheese in the bottom of each pepper.

Once steak is done, put about 1/4 cup steak into each pepper and top with cheese.

Continue layering steak and cheese, pressing down on the cheese each time.

Once full, place each filled pepper onto a baking sheet or in a deep pan.

Replace the tops on the peppers.

Cook in the preheated oven until peppers begin to soften and cheese is melted and bubbly, about 40 minutes.