In a skillet over medium heat, begin to cook the ground beef with the onion, celery, and green pepper. Stir and break up the meat as it cooks. Continue cooking until the meat is fully brown and the vegetables are soft, about 7 to 10 minutes.

Add the ketchup. Mustard, Worcestershire sauce, and water. Mix to combine. Reduce heat and simmer until slightly thickened, about 10 minutes.

Preheat oven to 350F.

Spray the bottom of a 9x13-inch or similar sized baking pan (see notes). Split the dinner rolls lengthwise by cutting (if necessary) with a serrated knife to form a top and bottom half. The individual rolls should remain connected together.

Place the bottom half of the bread in the prepared pan. Spread the sloppy joe mixture evenly over the bread in the pan. Use the top half of the bread to cover the mixture.

Bake uncovered for 10 minutes, then cover with a piece of foil and bake for 10 minutes more.

When finished baking, use a sharp knife to cut each individual roll from the group. The bottom will be crusty, so be sure to cut all the way through.

Serve and enjoy!