Instructions

  1. Slice the potatoes, peel and chop the onion and garlic, melt the butter in a large non-stick pan and sauté the onion and garlic for about 5 minutes, or until they are soft.
  2. Stir in the flour and cook for 1 minute.
  3. Remove the pan from the heat, add the stock, cream and thyme, and blend until smooth.
  4. Return the pan to the heat and bring to the boil, stirring occasionally, until the mixture thickens.
  5. Stir in half the parsley, the Worcestershire sauce and potatoes and simmer for 5 minutes, until heated through, stirring occasionally.
  6. Turn off the heat, stir in the egg yolk and season to taste with salt and freshly ground pepper.
  7. Sprinkle with the remaining parsley and serve.