This is basically a stew of that triumvirate of Spanish vegetables, onions, peppers and tomatoes. With the addition of something green, runner beans, asparagus, green beans or peas. As with many Spanish vegetarian dishes, originally they were not vegetarian, this would normally have some chopped chorizo, so carnivores feel free.
Slice onions and peppers and throw into a pan with some hot oil. Add salt and stir, turning heat down and using a heat diffuser cook slowly until soft and sweet. Add the fresh peeled and chopped tomatoes (this is best in the summer with fresh tomatoes, but canned will suffice), some herbs such as marjoram or thyme, a few chopped seeded guindilla peppers, some sliced garlic, pimenton and chopped parsley; cook for fifteen minutes until reduced and thickened. Add your chosen green vegetable, that has been blanched. Season. Put some in a casuela or any oven proof dish and create a dimple or two where you can crack an egg. Bake until the egg is cooked to your liking. Season the egg and garnish with a little freshly chopped parsley.