2-3 fl oz/60 to 80 ml Olive oil
1 large red (Spanish) onion, chopped
2 tablespoons plain Flour
16 fl oz/500 ml Milk
1/2 teaspoon Salt
1/8 teaspoon ground Nutmeg
2 lightly beaten Eggs
1 large eggplant (aubergine), peeled and sliced 1/4 in/6 mm thick (about 1 lb/500 g)
2 oz/60 g crumbled Feta cheese
4 oz/125 g grated mild melting cheese
2 tablespoons grated Parmesan cheese
1. In a 2-qt/2-l saucepan heat 2 tablespoons of the oil. Cook onion over medium heat in hot oil for 3 minutes. Stir in Flour and cook 1 minute; add Milk all at once. Cook and stir till thickened and bubbly. Stir in Salt and nutmeg. Stir 4 fl oz/125 ml of the milk mixture into beaten eggs; gradually stir egg mixture back into remaining milk mixture, stirring constantly. Cover and remove from heat.
2. Preheat grill. Arrange eggplant (aubergine) slices on a large baking sheet. Brush both sides of slices with the remaining 2-3 tablespoons olive oil. Grill slices 4 in/10 cm from heat for 8-10 minutes, or till golden brown, turning once. (If all slices do not fit on baking sheet, grill half the slices at a time.)
3. Arrange half the grilled slices in a greased 2-qt/2-l rectangular baking dish. Spoon half the milk sauce evenly over eggplant (aubergine). Sprinkle all the Feta cheese and half the mild melting cheese over sauce. Arrange remaining eggplant (aubergine) slices in a layer over cheeses; sprinkle with remaining mild melting cheese. Spoon remaining sauce over all; sprinkle Parmesan cheese on top. Bake, uncovered, in a preheated 350°F/180°C oven for 30 minutes, or till heated through.