Preheat the oven to 375°F (190°C).

Cook the lasagna noodles according to package instructions until al dente. Drain and set aside.

In a large skillet, heat the olive oil over medium heat. Add the chopped onion and garlic, sautéing until softened, about 3-4 minutes.

Add the ground turkey or chicken to the skillet. Cook until browned, breaking it apart with a spoon, about 5-7 minutes. Stir in the Italian seasoning, salt, and black pepper.

In a bowl, mix together the ricotta cheese, 1/2 cup of the Parmesan cheese, chopped spinach, heavy cream, chicken broth, and nutmeg until well combined.

In a 9x13 inch baking dish, spread a thin layer of the ricotta mixture on the bottom. Layer 4 lasagna noodles on top, followed by half of the meat mixture, and half of the remaining ricotta mixture. Sprinkle with 1 cup of mozzarella cheese.

Repeat the layers: noodles, meat mixture, ricotta mixture, and 1 cup of mozzarella cheese.

Top with the final layer of noodles, the remaining ricotta mixture, and the remaining mozzarella and Parmesan cheese.

Cover the dish with aluminum foil and bake for 25 minutes. Remove the foil and bake for an additional 15-20 minutes, or until the cheese is bubbly and golden brown.

Let the lasagna cool for 10 minutes before slicing and serving.