Shoulder of Lamb with Pommes Boulangère

This really does require the minimum of preparation, but dear God, it’s good. The lamb sits atop a tray of potatoes wallowing in stock, mixed with onion and a little thyme. As the meat cooks, slow and low, the juices infuse into the broth. You’ll end up with lamb that disintegrates very pleasingly. And some of the most seductive potatoes you’ll ever meet. You want to slice the potatoes about 1 cm