Preheat oven to 375 degrees F.
Cut aubergine in half lengthwise and scrape out flesh. Place in a mixing bowl and set aside. Heat oil in a 12 inch to 14 inch saute pan until smoking. Add leeks and cook until very soft, about 8 to 10 minutes. Add tomatoes and continue cooking for 2 minutes. Remove from heat and stir into aubergine mash. Add thyme, eggs and yolks and milk to bowl and stir to blend well. Season with salt and pepper and spoon into buttered 4 inch tall timbale molds.