Cut the roll into cubes and fry in a little butter. Melt the rest of the butter in a saucepan and mix with flour and add the broth and cream to this roux. Simmer for 10 minutes and then rub the cheese into the soup. Season with pepper to taste, even a pinch of sugar can be used. Alloy with the egg yolk. Add the parsley and paprika powder. Serve with the roasted bread rolls.