Beef wellington

Preheat the oven to 200C/Gas 6.

Season the beef fillet. Heat a little olive oil in a large sauté pan, then sear the beef over a high heat for a minute or two until caramelised on all sides. Remove from the pan and set aside.

Put the mushrooms and onion in a food processor and pulse to form a coarse paste. Scrape the mixture out into the frying pan that the beef was seared in. Cook over a high heat, stirring frequently until the vegetables have reduced by about two-thirds.

Lay the rolled out puff pastry in the middle of your work surface. When the mushroom mixture has cooled, spread it evenly over the pastry. Pat the beef fillet dry, and place in the centre of the puff pastry rectangle.

Brush the edges with beaten egg, then fold the pastry around the beef so that the joins lay on the underside of the fillet. Cut off any excess pastry, and press the seams together. Place on a baking tray and brush all over with beaten egg. Chill for 30 minutes.

Cut the remaining onions into wedges and arrange on a baking tray. Peel the carrots and add them to the onions (you may want to cut each carrot in half lengthways, depending on their size). Drizzle the vegetables with olive oil and season well. Roast in the oven for 30 minutes. At this point, take the tray out of the oven and remove the onion wedges from the tray and set aside. Put the carrots back in the oven for another 10-15 minutes, or until tender.

Take the wellington out of the fridge, then brush with beaten egg again. Bake in the oven for 20 minutes, then turn the oven down to 180C/Gas 4. Cook for 15 minutes, then remove the wellington and allow to rest for 15 minutes.

Peel the potatoes and cut them into equal sized pieces. Boil them in salted water until tender, then drain well. Push the potatoes through a ricer, then stir in the butter, cream and ½ tbsp sea salt. Keep warm until serving.

Meanwhile, melt about 25g butter in a sauté pan. Add the roast onion wedges, sprinkle over the sugar and the balsamic vinegar and toss over a medium heat until soft and caramelised.

To make the sauce, pour the port and madeira into a small frying pan. Bring it up to the boil, then allow to simmer until it has reduce by two-thirds. Pour in the beef stock and simmer until reduced by half again.

Just before serving, lightly steam the green beans and whisk the remaining butter into the sauce.