Peel and cut into thick shreds two Portugal onions, and fry them in a stewpan with a spoonful of oil, pepper, and salt, of a light-brown colour; they must be occasionally stirred with a fork in order not to bruise them, and when fried, add a gill of Tomata, No. 21, a piece of glaze, and the juice of half a lemon; boil gently for five minutes.