Preparation time: 15 minutes
Cooking time: 20 minutes
50g (2oz) butter
100g (4oz) leeks, finely sliced (about 1 large one)
Nutmeg, to taste
175g (6oz) fresh breadcrumbs, preferably a mixture of white and brown
2 tsp thyme, finely chopped
2 eggs, separated
1½ tsp English mustard
175g (6oz) Caerphillly cheese
2 tbsp milk
50g (2oz) flour
1 Melt half the butter in a frying pan and sweat the leeks over a medium heat until well softened. Season with salt, pepper and nutmeg.
2 Mix 100g breadcrumbs with the thyme and crumble in the cheese. Stir in the softened leeks. Beat the egg yolks and mustard together then add to the mix. Season, mix well and add the milk. Divide the mixture into six and shape into sausages then chill for half an hour.
3 Heat the oven to 180°C/R4. Whisk the egg whites until frothy. Put the egg whites, flour and remaining breadcrumbs on separate plates, and roll each sausage in the flour, then whites, then breadcrumbs to coat.
4 Melt the remaining butter in the pan over a medium-high heat. When hot, add the sausages and cook until just golden on each side. Transfer to a baking sheet and cook for about 20 minutes, until golden. Serve immediately.