2 medium eggplants (pale-purple eggplant, if available)
2 tablespoons EVOO, plus more for drizzling
Ground black pepper
1 pound ground beef
1 small onion, finely chopped
3 to 4 cloves garlic, finely chopped
1 small fresh chile, seeded and finely chopped, or 1 teaspoon crushed red pepper flakes
2 tablespoons tomato paste
1 cup beef orchicken stock
1 (28- or 32-ounce) can San Marzano tomatoes (look for DOP on the label)
A few leaves of fresh basil, torn
4 tablespoons (1/2 stick) butter
3 tablespoons flour
2 cups whole milk, warmed
Freshly grated nutmeg
Freshly grated Parmigiano-Reggiano cheese
Preheat the oven to 425°F.
Halve the eggplants lengthwise. With a small paring knife, score the flesh (without cutting through the skin) and cut around the edges of the eggplants, leaving a 1/4-inch-thick shell of flesh and skin. Scoop out the flesh with a spoon, leaving the eggplant shells for roasting.
Chop the eggplant flesh and season with some salt. Drain on a kitchen towel or paper towels.
Dress the eggplant shells with a drizzle of EVOO to coat the fleshy insides and season with a little salt and pepper. Roast on a baking sheet for 15 minutes, then remove from the oven. Reduce the oven temperature to 375°F.
Heat 2 tablespoons EVOO (2 turns of the pan) in a large skillet over medium-high heat. Add the beef, breaking it up into crumbles as it browns. Add the eggplant flesh, onion, garlic, chile, and salt and pepper and cook until softened, 7 to 8 minutes. Stir in the tomato paste. Add the stock and stir. Crush up the tomatoes and add to the pan. Add the basil, then reduce the heat a bit and simmer to thicken.
Melt the butter in a saucepan over medium heat. Whisk in the flour and cook for 1 minute, then whisk in the warm milk. Season with salt, pepper, and nutmeg and cook the sauce until thick enough to coat a spoon.
Fill the eggplant halves with the meat and eggplant mixture, dividing evenly. Pour some sauce over each eggplant half and top with a little Parm. Bake until bubbling and browned on top