For the hangover egg dish, dice the onion and fry in a pan on the stove. Cut the sausage into small pieces and add. Quarter the tomatoes and fry them as well.
Mix eggs with salt in a bowl with a whisk until well blended. Cut cheese into cubes. Pour the whisked egg into the pan and sprinkle the cheese cubes on top.
Stir the egg mixture with a spatula until the egg is completely set. Arrange on a plate and garnish with a dash of kernel oil.