WASH bell peppers; REMOVE 1- 1 1/2 inch off pepper tops levelly using a knife (reserve tops); REMOVE seeds and ribs from peppers with a tea spoon; PREHEAT oven to 350°F.
PREPARE your favorite recipe for quick-cooking rice, to yield 2 cups rice; BROWN 1 pound bulk Italian sausage in a skillet and drain fat.
INTO a large pot (with an accompanying vegetable steamer basket set aside) combine 2 cups water, 3 tablespoons white vinegar, 2 teaspoons salt and 1 teaspoon Italian seasoning; INSERT steamer basket into pot; PLACE peppers cut-side down, along with pepper tops, into steamer insert in pot; COVER; BRING to boiling; BOIL for one minute; REDUCE heat to medium high. STEAM until tender yet firm (about 10 minutes).
CAREFULLY remove peppers and tops from steamer basket using tongs and place onto onto paper towels to drain.
DICE pepper tops around the stems (discard stems); STIR in the diced peppers and cooked sausage to cooked rice, along with 2 tablespoons of the parmesan cheese, and 3 tablespoons sliced black olives.
POUR desired amount of marinara sauce into the rice/meat mixture to moisten; SEASON rice/meat mixture to taste with a little Italian seasoning and/or salt and pepper, if desired; BLEND.
POUR enough marinara sauce into an 8 x 8 x 2 square baking dish, just to cover bottom; ARRANGE the steamed peppers upright in baking dish.
STUFF peppers upright, mounding slightly, with the rice/meat mixture; POUR remaining marinara sauce over stuffed peppers.
DIVIDE and distribute shredded mozzarella cheese over prepared peppers; SPRINKLE peppers with remaining parmesan cheese; TOP center of peppers with a whole black olive (or olive slice).
BAKE peppers upright in a baking dish until heated through, about 10 minutes; SERVE and enjoy!