Boil a large pot of salty water. Add your pasta to the pot. Cook it until it is slightly firm. This is called al dente. Drain the pasta in a colander. Set it aside for later.

Place a skillet over medium heat. Melt the butter slowly. Add the minced garlic to the pan. Cook it for about one minute. Do not let the garlic turn brown.

Pour the heavy cream into the skillet. Let it simmer for five minutes. It should thicken up a little bit. Add the black pepper and nutmeg now. Nutmeg adds a very secret, rich flavor.

Turn the heat down to low. Stir in the grated Parmesan cheese. Keep stirring until the sauce is smooth. The cheese should be fully melted. Taste it to see if it needs salt.

Throw the fresh spinach into the sauce. Stir it gently for two minutes. The leaves will shrink and get soft. This adds color and great nutrients.

Put the cooked pasta into the skillet. Toss it well to coat every piece. Make sure the sauce fills the pasta tubes. It should look very creamy and green.

Grease your baking dish with cooking spray. Pour the pasta mixture into the dish. Spread it out evenly with a spoon.

Sprinkle the mozzarella cheese over the top. Cover the whole surface with white cheese. This creates a gooey crust in the oven.

Heat your oven to 375 degrees. Bake the pasta for 20 minutes. The cheese should be bubbly and brown. Serve it while it is steaming hot.