• 1 tbsp olive oil
• 25 g (1 oz) butter
• 600 g (1 lb 5 oz) pork loin
• 200 g (7 oz) rhubarb
• 100 ml (3½ fl oz) chicken stock
• 50 g (2 oz) sugar
• 1 tsp mustard
• 1 tbsp white wine vinegar
• sea salt and freshly ground black pepper

Preheat the oven to 190°C/375°F/Gas 5. Heat the oil and butter in an ovenproof pan and, when foaming, add the pork and brown on all sides. Place in the oven and roast for 25 minutes.

Meanwhile, trim the ends of the rhubarb and cut the stems on a diagonal into 4cm (1½-inch) lengths.

Remove the pork from the oven and lift out of the pan. Add the remaining ingredients to the pan, stir, then place the pork on top and return to the oven for a further 15-20 minutes, or until cooked through.

To serve, slice the pork fillet and serve with the rhubarb sauce.