Preheat oven at 170° C.

• Finely chop onions
• Chop peppers
• Coarsely chop spinach
• Grate cheeses

1.  In a pot with 3 liters of water boil the lasagna with the lemon juice for 7 minutes. Strain them and rinse them under the faucet.

2.  In a frying pan, sauté with the olive oil the peppers and the onions for 3 minutes. Place them in a bowl and let them cool off.

3.  In the same frying pan sauté for 5 minutes the spinach with a tablespoon of butter and add during sautéing salt and freshly ground pepper.

4.  In a pyrex dish place a layer of lasagna on the bottom. On top spread half the spinach and sprinkle half the parmesan. Add the sautéed red peppers and onions.

5.  Continue with the same sequence adding on every layer a bit of tomato sauce. Finally add on top the grated yellow cheeses. Bake for ½ hour.

6.  For the dish to be absolutely ready, you have to let it cool off for 10 minutes, so that the flavors can mix.