Step 1

Preheat oven to 150°C. Place the lamb on a clean work surface. Use a small sharp knife to cut eight 2cm-deep slits in the surface of the lamb. Place 1 rosemary sprig and 1 garlic slice in each slit. Sprinkle lamb with paprika and season well.

Step 2

Arrange onion in base of a roasting pan and top with lamb. Pour Guinness and stock around the lamb in the pan. Cover tightly with foil. Roast, basting the lamb with pan juices occasionally, for 6 hours or until lamb is falling off bone. Set aside, covered, for 20 mins to rest.

Step 3

While the lamb is resting, increase oven to 220°C. Line a baking tray with baking paper. Place brussels sprout on lined tray. Sprinkle with sugar. Drizzle with butter. Season. Toss to combine. Roast, turning occasionally, for 20 mins or until tender and golden, adding the tomatoes, baby broccoli and hazelnut to the pan for the last 5 mins of cooking.

Step 4

Transfer the brussels sprout mixture to a serving platter. Top with the lamb. Drizzle with any pan juices to serve.