Clean the mushrooms to get rid of any dirt or grit: some people use a brush, but I think the best way is to dab them carefully with a J-cloth. Leave the girolles whole and cut the ceps into 4-5 thin slices (so that they are the same size as the girolles).
Put the oil into a large pan on a medium heat and cook the girolles first, to cook off their water. Season the girolles, then add the ceps and let them caramelize a little (1–1½ minutes), then add the shallots and garlic. Cook gently for a couple of minutes, lowering the heat slightly to medium-low, then add the piquillos. Cook for a minute, just to bring everything together, then add the prawns and season again.
When the prawns are halfway cooked, add the whisked eggs and turn the heat up to medium-high. Leave for a second, then stir a little, leave again, then stir again – and repeat. The eggs are done when you can see that they are shiny but not liquid. Remember that they will continue to cook when you take them off the heat. Sprinkle over the parsley and serve with toast.