Preheat the oven to 190?/gas mark 5. Top and tail the carrots and cut into 1.5cm chunks leaving the skin on, place into a roasting tray with thyme, crushed garlic drizzle with rapeseed oil and season. Cover tightly with tin foil and roast for 30 minutes. Once cooked remove from oven, pop into a blender and puree until smooth. Make the pesto by combining pine nuts, Grana Padano and garlic in a food processor and blitz for a second or two. Add the truffle oil a little at a time with the motor running until combined and pesto-like. Finish with lemon juice and season to taste. Blanch beans and put into iced water to stop the cooking process.
Heat a cast iron pan on a high heat. Brush the chicken with oil, season and pan fry side skin down until golden brown. Turn and place in the oven for 25 minutes. Once cooked remove the chicken from the oven Transfer to a plate and spoon over half the pesto. In the pan juices, fry the green beans. Add the remaining pesto to the green beans and mix well. To serve, first make a pile of the root veg. Tip the green beans over this (making sure all the truffley pan juices are distributed onto the veg). Cut the chicken into two pieces and arrange on top. Serve with sautéed new potatoes or a creamy gratin.