Stuffed Onions

Preheat the oven to 375°F. Bring a large pot of water to a boil.
Trim the top and bottom off each onion, peel the skins, and remove the outer tough layers. Using a small knife, slice down one side of each onion from top to bottom, cutting just to the center without slicing through.
Boil the onions whole for 10 to 12 minutes until softened, then drain and let cool slightly.
For the filling, heat olive oil in a skillet over medium heat. Add the red onion and garlic and sauté for 5 minutes until softened.
Stir in the tomato paste, salt, oregano, and dried basil, and cook for 1–2 minutes until fragrant.
Add the lentils, rice, tomato, and vegetable broth. Stir to combine and cook for 3-5 minutes, then remove from heat.
In a separate bowl, whisk together the crushed tomatoes, vegetable broth, and olive oil to make the sauce.
Once the onions are cool enough to handle, separate them into layers.
Spoon the lentil mixture into each onion cup, and place the stuffed onions into a baking dish. Pour the tomato sauce around the stuffed onions, covering the base of the dish.
Cover tightly with foil and bake for 40 minutes. Then, uncover and bake for another 15–20 minutes until the onions are golden and tender, and the sauce has thickened.