Preheat oven to 160℃ (140℃ fan forced). Heat olive oil in a large flameproof casserole dish over high heat. Season lamb well with sea salt and pepper then sprinkle with flour. Cook the lamb for for 8-10 minutes or until well browned all over (we want lots of good colour on it). Transfer to a plate and set aside.
Reduce the heat to medium and add the onion, carrot, celery and garlic to the pan, cook, stirring often for 5 minutes or until lightly golden in colour. Pour in the beer and allow it to bubble up for 1 minute then stir in the honey, chicken stock and herbs. Bring to a gentle boil, then return the lamb to the pot, nestling it in between the vegetables, then cover with a tight fitting lid.
Transfer the lamb to the oven. Cook for 2 ½ hours, turning lamb twice during cooking time, or until lamb is very tender and almost falling apart. Carefully remove the lamb from the pot and transfer to a lined baking tray. Remove the elastic ties from the lamb (if it had them) and increase the oven temperature to 200℃ (180℃ fan forced).
Return lamb to the oven and cook for a further 20-25 minutes or until golden brown on top. Meanwhile, strain the vegetables and liquid from the pot into a saucepan through a sieve. Using a a spoon, push down (hard) on the vegetables to extract as much of the vegetables through the sieve as possible. Discard remaining solids in the sieve.
Place the pan juices over a high heat and bring to the boil. Boil rapidly until the sauce has reduced by half and thickened slightly. Season to taste with salt and pepper. Divide lamb (in large chunks) between serving plates. Spoon over pan juices and serve with baked baby chat potatoes, steamed green beans and some baby spinach leaves. Serve with remaining pan juices on the side.