Slice the eggplants, zucchini, and potatoes into ¼-inch rounds. Lightly sprinkle salt over the eggplant slices and let them rest for 30 minutes to draw out moisture.

In a large skillet, heat olive oil over medium heat. Fry the salted eggplant slices in batches until golden brown, about 3-4 minutes per side. Sauté zucchini until soft.

Sauté finely chopped red onion in olive oil until translucent. Add minced garlic and cook for 30 seconds. Stir in ground meat, cooking until browned.

Pour in red wine and simmer until almost evaporated. Stir in crushed tomatoes, cinnamon, nutmeg, and herbs. Simmer gently for 10-15 minutes.

In a saucepan, melt butter and whisk in flour to create a roux. Gradually add milk while whisking until thickened. Remove from heat and stir in egg yolks, nutmeg, and cheese.

Preheat oven to 350°F (175°C). Layer sliced potatoes, fried eggplant, zucchini, and meat sauce in a greased baking dish. Pour béchamel sauce evenly over the top.

Bake for 40-45 minutes until golden brown. Let the moussaka rest for 30 minutes after baking to set the layers.

Cut into squares or wedges for serving and enjoy warm, possibly with a Greek salad and crusty bread.