Jamie Oliver's Rioja poached fillet steak with potato and swede mash

Jamie Oliver did this in his book "jamie's kitcten" with barolo instead of rioja and celeriac mash instead of sede and potato....I find this book one of his most difficult and it is definately not a recipe for everyday, but I cooked it for a speical occasion for a sympathetic audiance ( becaue the sause did split at the end) and they loved it. I served it with green beans too.
Serves 41/2 swede3 large potatoes sea salt and freshly ground black pepper 4 x 150gr / fillet steaks, preferably organic and well marbled 570ml / 1 pint chicken stock 1/2 bottle Rioja5 cloves garlic, peeled and kept whole 1 small bunch fresh thyme 6 whole peppercorns 100gr / 3 1/2oz butter
First peel the swede and potato. Cut into rough 2cm/1 inch dice. Half fill a large saucepan with salted water and bring to the boil. Take another pan which will snugly fit your 4 steaks later, and add your chicken stock, wine, garlic, bunch of thyme, peppercorns and a pinch of salt. Bring this to the boil then lower the heat to a gentle simmer. By this time your pan of boiling water should be ready so add your celeriac, cover with a lid and boil fast for 15 to 20 minutes until it's tender.
Place your 4 steaks side by side into the simmering wine and stock, making sure they are well covered by the liquid. Add a little water if needed, but if the pan is nice and snug the steaks should be well covered. As soon as they are in the pan, it generally takes about 6 minutes to cook rare, 8 minutes for medium and 10 minutes for medium to well done. Depending on the thickness of the steaks and how cold they were when you put them in, there's always a bit of leeway in the timing, so the best thing to do is give them a little pinch to check how soft they are in the middle. Cover the pan with a lid, half on,
When cooked to your liking remove them to a warm plate, cover and leave them to rest for a couple of minutes while you drain your cooked vegin a colander. Place it back in the pan adding half the butter. Mash to a smooth puree and season well to taste.
To make a light sauce all you need is 2 wineglasses full of the poaching liquor - you can freeze the rest. Bring this to a fast boil, then remove the thyme and peppercorns, and mash up the garlic which will be soft and sweet. Allow to boil for a couple of minutes. Remove from the heat, season to taste and add the rest of the butter. Shake the pan lightly so the melted butter dissolves into the wine - this will make it a shiny lightly thickened sauce. Do not reboil as it will split. Serve each steak with a bit of mash and a little sauce. any leftover cooking liquor can be sieved and kept in the freezer to use again to make gravy from the goodness left in the roasting tray.
Enjoy!!!