Cook the spaghetti until it`s al dente, pour cold water over it, drain and pour into a baking dish.
Defrost and heat the spinach. Add the cream. When everything is boiling, add the parmesan and cream cheese to the spinach and wait until both have melted. Season to taste with salt, pepper and nutmeg.
Pour the sauce over the spaghetti and sprinkle with grated cheese. I use Emmentaler for this because I like it a little stronger in taste. But Gouda is also doing quite well.
Place the casserole in the oven preheated to 180 ° C and bake until the cheese has run and begins to turn brown.