Spinach lasagne

1 box dry lasagne about 1 pound
8 tbsp unsalted butter or 1/2 cup oil
1/2 cup all-purpose flour or 1/2 cup cake flour
4 cups whole milk or low-fat milk
1/2 tsp grated nutmeg or allspice
2 tbsp salt or reduced-sodium salt
1 tsp white pepper or black pepper
2 cups shredded mozzarella or jack cheese or Gouda
3/4 cup grated parmesan or Manchego
2 pounds fresh spinach chopped with stems

1. In a large saucepan, melt 4 tablespoons of butter and when it sizzles, add the flour and stir to form a paste; add the milk gradually, stirring constantly. Add the nutmeg and salt to taste and when the sauce has thickened, set aside.

2. In a large pot, place the chopped spinach (stems and leaves) with a sprinkle of water. Bring to a gentle simmer and set aside as soon as the leaves wilt and soften. Transfer to a large colander and drain thoroughly, in order to keep it damp but not wet. Place the spinach in a bowl, add two tablespoons of butter and salt to taste and mix gently to combine.

3. Bring 8 cups of salted water to a boil and cook the lasagne according to the package instructions. When the paste is cooked but still firm (al dente), drain it and started assembling the dish.

4. Butter a rectangular serving dish generously; ladle some white sauce, cover with cheese and spinach and add the lasagne. Keep layering with a coating of white sauce, cheese, pasta and spinach . Ladle white sauce and cheese over the last layer of lasagne. Right before serving, bake in a 350F oven for 30 minutes until the top is bubbly and a brown crust has formed and a knife inserted in the pasta comes out hot. Serve immediately.