The base was made, frying in olive oil 1 large chopped onion, and half of each red and Green pepper until soft. Add 3 médium sized washed and chopped courgettes. Stir thoroughly then add 2 tins of chopped tomatoes. Bring to the boil and simmer until the courgettes are soft and the sauce has thickened somewhat. Wash any type of White fish, salt lightly and lay on top of the pisto. Cover and continue simmering until the fish is cooked (10mins more or less).