Wrap the beef fillet tightly in cling film to get an even shape. Then cut into 4 portions and grind some black pepper on each end.
Place the sweet potatoes, carrots, shallots and garlic on an oven tray and drizzle with olive oil and some salt, and roast in a pre-heated oven at 180°C for 15-20 minutes.
Put a pan on a high heat and sear the beef fillet for 2-3 minutes on both sides. Transfer to an oven tray and put in the hot oven for 5 minutes (or more if you would like your meat well done). Remove from the oven and leave the meat to rest in a warm place for 2-3 minutes.
Meanwhile deglaze the steak pan with red wine and add the chicken stock. Reduce the liquid by at least half until it is a sauce like consisitency. Then stir in the butter to give it a rich gloss.
In another frying pan, sear the foie gras until caramelised on both sides.
To serve, remove the cling film from the meat and place the steak in the centre of a plate. Place the potatoes and vegetables around the steak and drizzle everything with the red wine jus and serve immediately.