Cut each eggplant into half, lengthwise. Scoop out the inner flesh leaving a thin layer making a shell or boat with the skin. Chop the scooped flesh into small cubes and set aside.
Pour 1 cup of the marinara sauce to a baking dish and spread evenly. Arrange the eggplant shells on top, cut part facing up. Drizzle with some olive oil and sprinkle with some salt, ground pepper, and Italian seasoning. Bake at 200°C for 15 -20 minutes.
In a skillet, heat olive oil over medium heat. Saute garlic and onions until tender and aromatic.
Add ground beef. Brown while breaking up lumps with a spoon for 3 minutes. Stir in the chopped eggplant flesh and cook for another 2 minutes or until tender.
Add the green bell pepper and the rest of marina sauce. Mix and let simmer for 2 minutes.
Stir in diced tomatoes. Season with Italian seasoning, salt and ground pepper. Cook for another minute then remove from heat.
Add the breadcrumbs and ¼ cup of shredded Parmesan and mix until well combined. Divide the filling into pre-baked eggplant boats.
Sprinkle top with the remaining shredded Parmesan cheese. Bake at 180°C for another 15 minutes until cheese melts and turns golden.
Remove from oven and garnish with basil before serving.