Cut the liver into thin pieces, add water and a few drops of vinegar. After it sits for a bit, wash and salt it. Drain well into a colander.
Mix some of the dried crumbing with flour and dip each piece. Fry on low heat and leave aside.
In a pot, saute the onions, peppers and zucchini, add the tomatoes and fry until ready, season with a little paprika, salt and parsley.