- Cube the potatoes; roughly chop the onion; quarter the mushrooms if you use the large one; half the tomatoes.
- In a large frying pan, heat the half of the oil then add onion and mushrooms and fry for 15 minutes or until golden. With the help of slotted spoon, remove them and set aside. Put remaining oil and fry the potatoes for about 6 minutes until golden.
- Turn up the heat, stir in the tomatoes and fry at a high heat for about 3 minutes until it is lightly golden. Put onion and mushrooms in the pan again.
- Make 4 wells in the mixture and break the egg and put an egg in each hole. Place over the cheese and put under the preheated grill for about 5 minutes until the eggs are set and the cheese bubbling and golden.
- Drizzle over the parsley and serve immediately.