Preheat your oven to 375°F (190°C).
Bring a pot of salted water to a boil and cook the lasagna noodles until al dente, then drain and set aside on a non-stick surface.
In a medium skillet over medium-high heat, brown the ground beef with minced garlic, sea salt, and black pepper until no longer pink.
Stir the fresh baby spinach into the beef until it is completely wilted, then remove the skillet from the heat.
In a small mixing bowl, combine the ricotta cheese, liquid egg whites, and dried oregano, stirring until the mixture is smooth and well incorporated.
Spread 2 tablespoons of the marinara sauce across the bottom of a small, individual-sized baking dish.
Place one-third of a lasagna noodle sheet (cut to fit) over the sauce, followed by a layer of the beef and spinach mixture, a dollop of the ricotta mixture, and a spoonful of sauce.
Repeat the layering process until all ingredients are used, finishing with a final layer of noodle, the remaining marinara sauce, and a sprinkle of shredded mozzarella.
Cover the dish tightly with foil and bake for 20 minutes.
Remove the foil and bake for an additional 10 minutes until the cheese is melted and the edges are slightly crispy.