Cut the eggplants in half lengthwise. Score the flesh in a crisscross pattern, drizzle with olive oil, sprinkle with salt, and roast at 180ºC (350ºF) for 25–30 minutes.
While roasting, prepare the sauce: sauté onion, garlic, leek, and carrot, add minced meat, season with salt, pepper, oregano, and thyme, then add tomato and simmer until thickened (about 40 minutes).
Scoop out the eggplants, leaving about 1 cm of flesh attached to the skin. Chop the removed flesh and mix it into the sauce.
Fill the eggplants with the sauce and return them to the oven for 5 minutes to heat through.