Preheat the oven to 200ºC with heat up and down. Gently wipe the mushrooms with a damp cloth or kitchen paper and remove the foot carefully, scraping the filaments a little with a spoon. Reserve the feet for another recipe or chop very finely to lightly sauté them with a little oil and mix with some tomato for the base of the filling (optional).
Paint with oil on the outside and season on the inside with garlic, onion powder, thyme or oregano, salt and pepper. Arrange in a greased baking dish or with aluminum or non-stick foil and bake about 8-10 minutes, until lightly cooked.
Take out of the oven, Cool slightly and fill with a little crushed tomato, or chopped, or homemade sauce that we have in the fridge (you can also use ratatouille, even peeled and chopped natural tomato). Season with a little more herbs or pepper and salt, and carefully crack an egg inside.
Give a hit of pepper and bake until the eggs have set to taste, preferably leaving the yolk honeyed to be able to break it and that it melts with the mushroom.