Preheat the oven to 190°C. Heat the oil in a large pan ovet medium heat. Add the onion and cook for about 3 minutes, until translucent. Add the mushrooms and cook for about 5 minutes, until lightly browned.

Stir in the ham, spinach and tomato and cook for a few minutes, until the spinach is heated through. If any water from the spinach accumulates in the pan, carefully drain. Season with pepper.

Divide the mixture amoun two over-safe ramekins/bowls that have been lightly greased with butter. Carefully crack an egg into each, making sure to keep the yolks intact. Place the ramekins/bowls on a baking tray and bake until the whites are just set but the yolks are still runny, about 10 minutes.