1. Pre heat oven to 160C. Trim any excess thick fat off the ribs if necessary and cut it in to smaller pieces between the bones for easier handling. Season well with salt and pepper
2. Heat a frying pan on high until very hot, add a little cooking oil, brown the ribs on all sides then place in an oven dish.
3. Reduce the heat on the pan and use it to caramelise the onion, carrots and celery slightly. Add them to the oven dish along with the wine and stocks, peppercorns, garlic and thyme. Make sure the ribs are just covered with the liquid; if necessary add a little water. Cover with a lid or tinfoil, place in the preheated oven and cook for 2½-3 hours. Check the meat by piercing with a small knife or fork after two hours, if the knife or cutlery goes in easily, the meat is ready.
4. Remove the dish from the oven and cool for one hour or so. Remove the ribs from the tray to a plate, cover and refrigerate for later.
5. Strain the sauce through a fine sieve into a pot or container and let it rest in the fridge until all the fat sets on top. Remove from the fridge and use a spoon to scrape the fat off. Reduce the sauce to a silky consistency. Return to the fridge until required.
6. For the mash, boil the potatoes in well-seasoned boiling water until completely cooked and soft, strain over a sieve and leave the potatoes to steam dry for a couple minutes. Push the potatoes through a fine sieve into a pot. Return the pot to a low heat and add a third of the butter, mixing well with a wooden spoon until the butter is well incorporated. Add the remaining butter and milk and mix until combined. Set the mash aside until required.
7. To prepare the carrots, preheat the oven to 220C. Melt the butter in a large oven-proof frying pan and add the carrots. Season well with salt and sprinkle with a pinch of sugar. Place the pan in the oven and toss every 5 minutes until the carrots are caramelised and soft.
8. For the onions, melt the butter in a medium-size pot and add the peeled onions, garlic, thyme, a sprinkling of salt and a sprinkling of sugar. Caramelise over medium heat until a light-brown colour, then deglaze the pan with the white wine.
Cook until the liquid has reduced by a third then reduce the heat, cover with a little water and continue to simmer until the onions are soft like a cooked potato.
9. To serve, return the beef cooking liquid to a pot and reduce on a low heat until the sauce is thick and silky. Reheat the ribs by placing them in the reduced sauce, simmer for 15 minutes or until hot through. Reheat the mash if necessary, adding a little milk to loosen the mixture if required. Finish the carrots with chopped parsley.
Place a spoonful of the mashed potato in the centre of a large deep plate or bowl, top with a short rib and pour a generous amount of sauce over and around it, arrange carrots and onions to the side. Serve immediately.
