- With one rack in the bottom third of the oven and a second rack in the top third, preheat the oven to 425°F (220°C).
- In a 13 x 9-inch (33 x 23 cm) baking dish, toss the potatoes with 1 tbsp (15 ml) of the oil. Season with salt and pepper. Spread the potatoes out in the baking dish.
- In a large bowl, combine the eggplants, garlic, oregano and remaining oil. Season with salt and pepper. Spread the mixture out in a non-stick or parchment paper-lined baking sheet, slightly overlapping the eggplant slices.
- Bake the potatoes on the lower rack of the oven and the eggplant on the upper rack for 30 minutes or until the eggplant slices are tender and golden and the potatoes are starting to soften. Let cool. Cover the potatoes with the eggplant mixture. Set aside. Lower the oven temperature to 375°F (190°C).
- Meanwhile, in a large, deep skillet over high heat, cook the ground meat in the oil with the cinnamon and cayenne, breaking the meat up with a wooden spoon, until browned, about 8 minutes. Season with salt and pepper. Place a strainer over a bowl. Drain the meat. Remove 3 tbsp (45 ml) of the cooking fat from the bowl and place in the skillet.
- In the same skillet over medium heat, lightly brown the onions in the cooking fat, stirring often, about 5 minutes. Add the garlic and cook for 2 minutes. Add the tomato paste and paprika. Cook for 1 minute while stirring. Deglaze with the white wine. Let reduce until almost dry. Add the tomatoes. Crush the tomatoes with a wooden spoon. Return the ground meat to the skillet. Simmer for 15 minutes or until the mixture thickens. Adjust the seasoning. Spread over the eggplant layer in the baking dish.
- In a pot over medium heat, melt the butter. Add the flour and cook for 1 minute while whisking. Whisk in the milk. Add the nutmeg. Bring to a boil while stirring constantly. Simmer gently for 1 minute or until thickened. Remove from the heat. Add the cheese and egg yolks. Adjust the seasoning. Pour the béchamel over the meat filling and spread out using a spatula.
- Bake on the upper rack of the oven for 20 minutes or until the béchamel is slightly golden. Finish off under the broiler, if desired. Let sit for 15 minutes before serving.
You can assemble the moussaka the night before you plan to bake it. In this case, add 10 to 15 minutes to the cooking time indicated in step 8.