Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.
Slice the eggplant into 1/2-inch thick rounds, lightly brush with olive oil, and roast for 15 minutes until softened.
In a skillet over medium heat, brown the ground beef with the diced onion and minced garlic until the meat is fully cooked.
Stir in the tomato puree, sea salt, black pepper, cinnamon, and dried oregano, then simmer for 5 minutes to meld the flavors.
In a small bowl, whisk together the Greek yogurt, egg, and parmesan cheese until the mixture is smooth.
In a small baking dish, layer half of the roasted eggplant, followed by the meat sauce, and then the remaining eggplant.
Spread the yogurt custard evenly over the top layer of eggplant.
Bake for 20-25 minutes until the topping is set and beautifully golden brown.