- 50g butter
- 100g leeks, finely sliced (about 1 large one)
- Nutmeg, to taste
- 170g fresh breadcrumbs, preferably a mixture of white and brown
- 2 tsp thyme, finely chopped
- 2 eggs, separated
- 1½ tsp English mustard
- 175g caerphillly
- 2 tbsp milk
- 50g flour
- Melt half the butter in a frying pan and sweat the leeks over a medium heat until well softened. Season well with salt, pepper and nutmeg.
- Mix 100g breadcrumbs with the thyme, and beat the egg yolks and mustard together. Crumble the cheese into the breadcrumb mixture and stir in the leeks, followed by the egg yolks and mustard. Season, mix well and add the milk.
- Shape into six sausages (damp hands will make this easier) and chill for half an hour.
- Heat the oven to 180C/350F/gas mark four. Meanwhile, 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.
- 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 richly golden. Serve immediately.