Step 1

For the sausages, melt the butter in a large non-stick frying pan and fry the leek gently for 8-10minutes, or until very soft but not coloured.

Step 2

Put 100g/3½oz of the breadcrumbs, the parsley, thyme and cheese in a large mixing bowl and mix until well combined. Beat the egg yolks with the mustard, salt and plenty of freshly ground black pepper in a separate bowl.

Step 3

Remove the frying pan from the heat and tip the leeks into the bowl with the breadcrumbs. Add the egg yolks and mix together well with a large wooden spoon until well combined. Divide the leek mixture into eight portions and roll into sausage shapes. Place the sausages onto a tray lined with clingfilm.

Step 4

Whisk the egg whites lightly in a bowl with a large metal whisk until just frothy. Sprinkle 40g/1½oz breadcrumbs over a large plate. Dip the sausages one at a time into the beaten egg and roll in the breadcrumbs until evenly coated, then place on the baking tray. Chill the sausages in the fridge for 30 minutes.

Step 5

Meanwhile, for the relish, heat the oil in a large non-stick saucepan and fry the onions for 20 minutes, or until very soft and just beginning to colour. Add the chilli and garlic to the pan and cook for a further five minutes, stirring regularly.

Step 6

Sprinkle with the sugar and pour over the vinegar. Bring to a simmer and cook for five further minutes, or until the liquid is well reduced and the relish becomes thick and glossy. Remove from the heat, set aside to cool for a few minutes then tip into a serving dish.

Step 7

Heat the oil into a large non-stick frying pan and fry the sausages over a medium heat for 10-12 minutes, turning regularly until golden-brown and crisp. Serve the sausages with a good spoonful of chilli and onion relish and some thinly sliced runner beans.