Slow cooked Lamb Shoulder is one of life's great comforts. And fragrant rosemary and sweet redcurrant jelly are classic pairings for a reason. It really is worth trying to start this dish the day before, but as long as you leave the lamb with the rub for at least 30 minutes (leave at room temperature for anything under an hour), you'll still have a great dish. It might seem like it's a long time cooking, but all the effort is done and dusted within 20 minutes. Just stick it in the oven and get on with your day until it's time to get get cooking the rest of the meal. For extra indulgence, reduce a bottle of wine by half (in a…