Preheat your oven to 400°F and line a large baking sheet with parchment paper.
Slice the eggplant into 1/2-inch thick rounds, sprinkle them with sea salt, and let them sit for 10 minutes to draw out moisture before patting dry with a towel.
In a shallow bowl, whisk the egg; in a separate shallow dish, combine the almond flour, garlic powder, and dried oregano.
Dip each eggplant slice into the egg wash, then dredge in the almond flour mixture until lightly coated, and place on the prepared baking sheet.
Bake the eggplant for 20 minutes, flipping halfway through, until the edges are golden and the centers are tender.
While the eggplant bakes, heat the olive oil in a skillet over medium heat and brown the ground turkey until fully cooked.
Stir the marinara sauce and black pepper into the turkey, allowing it to simmer on low for 5 minutes.
To assemble the stacks, place a spoonful of the turkey-marinara mixture onto an eggplant slice, top with a portion of mozzarella, and repeat with a second eggplant slice and more sauce.
Sprinkle the top of each stack with parmesan cheese and return to the oven for 5 minutes until the cheese is bubbly and melted.