Take your meat out of the fridge about an hour before cooking to bring it to room temperature.

Pre-heat the oven to 200C/Gas 6/180C fan

Using a sharp knife, make 8 incisions all over the joint and stuff each one with an anchovy half, garlic slice and some rosemary. Push in well so that the flavours can penetrate the meat.

Put the lamb joint into a roasting pan and season with salt and freshly ground black pepper. Place in the oven and roast for 15 minutes.

Meanwhile, boil the potatoes until they are just tender. Drain and shake in the pan to rough up the edges.

Take the meat out of the oven and add the par-boiled potatoes, butternut squash and onion wedges. Lift up the meat if you like to place some underneath if you need more room in the pan.

Pour some olive oil over the vegetables along with the lemon juice and season with salt and freshly ground black pepper. Return to the oven for 45 minutes.

Add the on the vine tomatoes to the roasting pan and cook for 15 minutes.

Remove the meat and leave to rest on a warm plate and covered with foil – about 15 -20 minutes.

Return the vegetables to continue roasting.

Slice the lamb and serve with the roasted vegetables and your choice of spring vegetables.