Put the pieces of salmon on the spinach (I forgot to take a picture of this step), a little salt and pepper.
Pour half the sauce. Repeat the layers, first the dough sheets, the remaining spinach, pieces of salmon. A little salt, pepper, cover with dough and pour the second part of the sauce. Sprinkle liberally with grated Parmesan.
Bake at 180 ° for 40 - 45 minutes until Browning. Look at your oven, if your oven bakes strongly, it is better to cover with foil. Less time to bake is not necessary, the lasagna is high, the fish may remain raw.