Not exact on measurements here - it’s just something I throw together.
Slice the tops of tomatoes (thin slice near top) and scoop our pulp and seeds; discard seeds, chop pulp. The “shell” should be about 1/2-inch thick.
Sprinkle salt and pepper inside shells and invert on paper towels to drain.
Saute chopped onion in a bit of butter until tender; add reserved pulp cooking until most of the liquid has evaporated. Remove from heat and stir in cooked rice (great use for leftover rice!), grated Precorino Romano (or Parmesan), parsley, basil and garlic salt.
Stuff tomato shells and dot with butter. Place in greased casserole and bake at 350* F. 15 to 20 minutes or until heated through.
If desired, place dry bread crumbs on top before dotting with butter.