Clean the leeks and cut into chunks. Peel and finely dice the onions. Crumble the Roquefort. Heat the butter in a frying pan. Add the leek and onions and fry for two minutes, stirring all the time. Pour on the stock and season with pepper. Cover and cook for 30 minutes.
Preheat the oven to gas mark 8, 240°C.
Drain the leeks and share them between 6 ramekins. Sprinkle them with crumbled Roquefort. Pour the cream over the top and grind on some pepper. Break an egg into each ramekin and place in the oven. Cook for 5 to 6 minutes until set.
Serve straight from the oven.
Add a pinch of ground nutmeg to each ramekin before cooking.
If serving vulnerable groups, elderly people, toddlers, pregnant women and people who are unwell, cook eggs until the whites and yolks are solid.