Preheat the oven to 350 ℉.

Bring a large pot of salted water to a boil and boil the lasagna noodles according to the package. While the water is boiling and the noodles are cooking, make the cheese and meat filling.

In a frying pan, brown the ground beef. Reserve 2 Tablespoons of beef fat and strain the meat, putting it on a plate lined with paper towels to drain even more. Saute the onions and spinach in the frying pan with the beef fat until the spinach is soft and the onions are turning brown. Stir in the garlic and keep stirring for one more minute. Stir the meat back into the pan and mix the meat with the onions and spinach. Then stir in the tomato sauce and bring to a simmer. Simmer for five minutes and set the pan aside.

In a large bowl, use a fork to blend the sour cream, cream cheese, and 1/2 cup of parmesan cheese until well combined. Set aside.

Once the noodles are done, and the cheese and meat are ready, begin layering the lasagna in a 9"x13" pan. Place some tomato sauce on the bottom of the pan, then layer with three lasagna noodles, 1/3 of the cheese mixture, and a 1/3 of the meat. Do the same with the second and third layers. Top the third layer with the last 1/4 cup of parmesan cheese. Bake for 45 minutes or until the top is golden and bubbly.