Onions peel and cut into fine slices. Wash and halve the tomatoes. Peel the skin from the chorizo and cut the sausage into slices.
Heat the oil in a large pan (with lid). Fry the chorizo in it while turning. Fry the onions briefly, then add the tomatoes and braise for about 2 minutes. Season with salt and pepper.
Beat the eggs one by one and put them into the pan. Cover and fry over medium heat for 4-6 minutes. Wash the basil, shake dry, pluck off the leaves, chop coarsely if necessary. Season eggs with salt and pepper. Sprinkle basil over them. Farmhouse bread tastes good with it.