Heat the oven to 160°C (140°C fan, gas mark 4). In a large roasting tin, add the oil, a third of the potatoes in one layer, season well and top with a third of the onions and one of the bay leaves, repeat with the rest.
Set the lamb leg on top, rubbing it all over with some sea salt and freshly ground black pepper. Add the potatoes and half bulbs of garlic to the tray, with the flat side of the garlic facing upwards. Pour the chicken stock on top, place the tray in the oven and roast for 4 hours, until the meat is tender.
For the dressing, mix all the dressing ingredients until combined, lightly season with sea salt and freshly ground black pepper. Bring a saucepan of water to the boil, add the Tenderstem® and cook for 1 ½ mins. Drain then toss with the watercress and a few spoonful’s of the dressing to serve.
Place the Tenderstem® and dressing in a large dish and serve the lamb in the roasting tray.
Nutrition analysis of recipes featured on the Tenderstem® website is calculated by a registered dietitian using McCance and Widdowson's The Composition of Foods, Seventh Edition, but may vary slightly depending on the specific ingredients used. Analyses do not include optional ingredients or suggested accompaniments unless specific amounts are given. If there is a range in the amount of an ingredient, the smaller amount is used. When a recipe lists a choice of ingredients, the first is used.