Slice the two large eggplants into ½-inch rounds, then sprinkle with salt and let sit for 30 minutes. Rinse and pat dry.

Preheat your oven to 400°F (200°C) and arrange eggplant slices on a baking sheet. Roast for 20-25 minutes until tender and lightly browned, flipping halfway.

In a large skillet, sauté chopped onion and minced garlic in olive oil for about 5 minutes until softened.

Add 1 lb of ground beef and cook until browned. Stir in crushed tomatoes, tomato paste, cinnamon, oregano, salt, pepper, and beef broth. Simmer for 15-20 minutes until thickened.

In a saucepan, melt 3 tbsp of butter over low heat. Whisk in 3 tbsp of flour and cook for about 2 minutes.

Gradually pour in 2 cups of warm milk while whisking continuously to avoid lumps. Cook until the sauce thickens for 5-7 minutes. Stir in 1 beaten egg and a pinch of nutmeg.

In a greased baking dish, layer half of the roasted eggplant, followed by half of the meat sauce. Repeat with remaining eggplant and meat sauce, then top with béchamel sauce.

Preheat oven to 375°F (190°C) and bake Moussaka for about 45 minutes until the top is golden brown and bubbly.

Remove Moussaka from the oven and rest for 10-15 minutes before slicing into squares and serving warm.