Canola oil, for frying
6 Japanese eggplants (about 2 lbs.),
4 tbsp. unsalted butter
1 lb. ground lamb
1 tbsp. tomato paste
1⁄2 tsp. ground cinnamon
6 cloves garlic, thinly sliced
1 small yellow onion, roughly chopped
1⁄2 green bell pepper, cored, seeded,
and finely chopped
2 medium tomatoes, cored and finely chopped
1⁄2 cup chopped flat-leaf parsley
1⁄4 cup chopped mint leaves
Kosher salt and freshly ground black pepper,
1. Pour oil into a 12" skillet to a depth of 1⁄2". Heat over medium-high heat until the oil is shimmering and very hot. Working in 2 batches, fry eggplants, turning occasionally, until softened, 6–8 minutes per batch. Transfer eggplants to paper towels to let drain; discard oil and set aside.
2. Melt butter in a 12" skillet over medium-high heat. Add the lamb and cook, breaking the meat into small pieces with a wooden spoon, until lamb is browned, about 8 minutes. Add the tomato paste, cinnamon, garlic, onions, and peppers and cook, stirring frequently, until onions are soft and golden brown, about 8 minutes. Add the tomatoes and cook until they're soft, about 6 minutes. Stir in the parsley and mint and season with salt and pepper. Remove skillet from heat and set lamb filling aside.
3. Heat oven to 475°. Halve reserved eggplants crosswise to make 12 pieces. Working with one piece at a time, cut a lengthwise, 1⁄4"-deep incision in the eggplant to make a pocket (be careful not to cut all the way through the bottom). Lightly season inside of each eggplant pocket with salt and pepper and spoon about 1⁄4 cup lamb filling into it, pressing filling lightly into pocket.
4. Arrange stuffed eggplants in a 9" x 13" baking dish and bake until hot, about 5 minutes. Serve warm.