01 -
Preheat oven to 400 degrees Fahrenheit for toasting the buns.
02 -
Place ground beef in a large sauté pan over medium-high heat. Add diced onions and green bell peppers. Stir thoroughly and break up the beef as it cooks.
03 -
Once ground beef is cooked through and no pink remains, drain excess grease from the pan.
04 -
Add water, brown gravy mix, salt, and black pepper to the pan. Stir well to combine, allow mixture to simmer and thicken for 3 minutes.
05 -
Stir mixture again and reduce heat to low to keep warm.
06 -
Arrange brioche buns, sliced side up, on a baking sheet. Place in oven and toast for 4 to 5 minutes until lightly golden.
07 -
Remove the pan from heat and add shredded mozzarella and cheddar cheese blend. Stir until cheese melts and is well incorporated.
08 -
Divide the meat mixture evenly and scoop onto toasted buns. Serve immediately.