French onion soup

Instructions

1. Melt half the butter in a shallow, heavy - based frying pan. Add the sliced onions, salt and pepper and press a piece of buttered paper on top. Cover and cook gently, stirring occasionally, for 20 - 30 minutes or until the onions are very soft. Remove the paper and continue cooking, stirring regularly, for a further 20 minutes or until caramelised; don't allow them to burn.
2. Meanwhile, in a separate frying pan, melt 20 g butter over low – medium heat. Add the whole onion and cook, turning regularly, until golden all over. Sprinkle with the sugar and cook gently until very dark brown all over.
3. When the sliced onions are nicely caramelised, add the whole caramelised onion and cook together for a few minutes, then add the stock and simmer for 30 minutes. Remove the whole onion and reserve for another use such as stock.
4. Preheat the oven to 150˚C. Place the bread slices on a baking tray and bake until dry and slightly browned. Swap the oven setting to grill function. Brush the toasted bread slices with the remaining butter.
5. Pour the soup into heatproof serving bowls and put 2 - 3 slices of bread in each bowl. Push down slightly so the bread slices are slightly covered with the soup, then sprinkle generously with grated gruyere and grill until the cheese is golden and bubbling.
6. Mix the egg yolks and port together until well combined. Lift the side of the browned topping and add 1 tablespoon of port mixture to each bowl. Serve at once. It must be scalding hot.