Cook the pasta in boiling salted water for about 8 minutes. Clean, wash, drain and roughly chop the spinach. Peel onions and garlic and chop finely. Fry them in hot oil until golden brown.
Add hack. Season with salt and cayenne pepper. Fry for approx. 5 minutes, turning. Stir in tomato paste. Add spinach and steam until it has collapsed. Flavour again. Cut mozzarella into very thin slices.
Pour some chopped spinach mixture and noodles into a casserole dish. Spread half of the mozzarella on top. Pour in the remaining ingredients and cover again with slices of mozzarella. Sprinkle with pine nuts.
Bake in the preheated oven (electric: 225 ° C/ gas: level 4) for about 12 minutes.