3 garlic cloves, thickly sliced, plus a whole bulb, halved
5 tbsp plain flour
200ml white wine, plus a splash
600ml lamb stock
Heat oven to 160C/140C fan/gas 3. For the lamb, scatter the vegetables, bay leaves and a few rosemary sprigs into a large roasting tin and drizzle with the olive oil. Use a sharp knife to make little slits all over the lamb. Poke a slice of garlic and a small sprig of rosemary into each one. Sit the lamb on top of the veg in the roasting tin, add a splash of wine, then cook for 2 hrs if you like it pink, or 2 hrs 15 mins for cooked through. Remove from the oven, transfer to a board and cover with foil, then rest for 45 mins-1 hr.
To make the gravy, pour off most of the fat from the tin but leave the veg and any meat juices. Place the tin on the heat to caramelise the veg, then stir in the flour and cook to a paste. Gradually stir in the wine, cook for a min, then stir in the stock and simmer until you have a tasty gravy. Push the gravy through a sieve into a small pan and keep warm.
Turn oven up to 220C/200C fan/gas 7. For the crumbs, blitz everything in a food processor and scatter over a tray. Bake in the oven for 10-15 mins until crisp, then re-blitz or break up with your fingers to crumbs again. These can be made in advance and kept in an airtight container for 2 days. Serve the lamb carved into slices, sprinkled with crumbs and a jug of gravy alongside.