Eggplant does double duty in this hearty dish -- baby eggplants are stuffed with a sweet-and-savory lamb filling, and Italian eggplant is paired with roasted red peppers for a bright, smoky relish.
Make the bell pepper and eggplant relish: Preheat oven to 350 degrees. Brush eggplant all over with 2 tablespoons oil and season with a pinch of salt. Place cut-sides down on one half of a rimmed baking sheet. Place garlic cloves and onion in the center of a 12-inch piece of parchment-lined foil. Drizzle with remaining 2 tablespoons oil and season with salt and black pepper. Toss to combine. Wrap to enclose and place on the other side of the baking sheet. Bake until eggplant is very tender, about 20 minutes. Set aside to cool. Add cooled eggplant and roasted garlic and onion mixture, along with 2 teaspoons salt, 1/4 teaspoon black pepper, and remaining ingredients, to a food processor; process until smooth.
Make the stuffed eggplants: Preheat oven to 350 degrees. In a large bowl, toss eggplants with 1/4 cup oil, then transfer to a rimmed baking sheet. Bake, tossing every 5 minutes, until very tender, 20 to 25 minutes. Set aside to cool.
Heat remaining 1 tablespoon oil in a small skillet over medium. Add scallions and garlic and cook until softened. Set aside to cool.
Meanwhile, place rice in a bowl and add enough water to cover. Swirl water to rinse rice and drain. Repeat process 3 to 4 more times until water is clear. Cover rice with clean water and soak for 30 minutes, then drain.
In a medium bowl, combine cooled scallion and garlic mixture, freekeh, date paste, tomato paste, spices, parsley, and mint. Season with 3/4 teaspoon salt and a pinch of black pepper. Stir in lamb.
Once eggplants are cool enough to handle, use a paring knife to cut a slit in each eggplant from top to bottom, taking care not to cut all the way through. Carefully open each eggplant and fill with about 1 tablespoon lamb mixture.
Place stuffed eggplants in a baking dish large enough to hold eggplants in a single layer and bake until filling is thoroughly cooked, 15 to 20 minutes.
Meanwhile, combine drained rice, 2 cups water, and 1/2 teaspoon salt in a large saucepan. Bring to a boil and cook until rice is just tender, about 5 minutes. Drain rice in a colander.
Whisk together tahini and lemon juice until smooth in a small bowl. Thin with 1 to 2 tablespoons water, if necessary, and season with salt.
Transfer rice to a serving platter and top with eggplants. Serve with tahini sauce and bell pepper and eggplant relish.