Remove stems from tomatoes and cut tomatoes in half crosswise, then scoop into a medium bowl the pulp and seeds from the tomatoes, leaving the shells about a 1/4-inch-thick.
Turn the tomatoes upside down on a paper towel lined plate and let them drain for 20 minutes.
While they are draining chop the tomato pulp and set aside.
Take a saucepan and heat oil over medium-high heat, then cook and stir the white parts of onions for 1 to 2 minutes in the hot oil until onion whites are wilted, then add bulgur and cook for 3 to 5 minutes until the bulgur is browned.
Add the tomato pulp that was set aside to bulgur mixture, along with water, lemon juice, and mint.
Bring the mixture over high heat to a boil and then reduce the heat to medium low, cover and let the mixture gently simmer for 15 to 20 minutes until the liquid has become absorbed.
Add the green onions and stir into the bulgur mixture, setting aside a few sliced green onion tops to garnish the stuffed tomatoes.
Add salt and pepper to the mixture depending on desired taste and spoon mixture into tomato cups.
Preheat the oven to 400 degrees F.
Place filled cups on a 13 X 9 inch baking dish and bake the tomato cups for 15 minutes or until they are heated through, then top with reserved onion tops, garnishing if desired, and immediately serve.