Preheat your oven to 375°F (190°C).
In a non-stick skillet over medium heat, brown the ground beef until fully cooked, then drain any excess fat.
Stir the marinara sauce, dried oregano, garlic powder, sea salt, and black pepper into the beef and simmer for 5 minutes.
In a small bowl, combine the ricotta cheese, egg white, and finely chopped baby spinach until smooth.
Boil the whole grain lasagna noodles in salted water according to package directions until al dente, then drain and pat dry.
In a small individual-sized baking dish, spread a thin layer of meat sauce on the bottom.
Layer with a portion of the noodles, half of the ricotta mixture, and a sprinkle of mozzarella cheese.
Repeat the layers, finishing with the remaining meat sauce, mozzarella, and grated parmesan cheese.
Cover with foil and bake for 20 minutes, then remove the foil and bake for an additional 10 minutes until the cheese is golden and bubbly.