Dip the squid carcass in boiling water for 2 minutes. Cut the squid meat into 5-7 mm thick rings.
Place the squid and onion in a salad bowl and sprinkle with lemon juice. Stir to marinate the two while you prepare the rest of the ingredients.
Fry the bell peppers in a frying pan for 3-4 minutes, add the mushrooms and fry them until golden brown. Do not salt the mushrooms or cover them with a lid, so that they do not release juice and remain dry. Place all the ingredients in a bowl with the salad. Add salt and a mixture of spices to taste, mix everything well. Place the finished salad on portioned plates.