I have a constant supply of stock in my freezer it makes a base for my soups, stews, pies, sauces and risotto. You can lamb bones easily enough from your butcher or meat supplier at your local farmers market.
Prep: 5 minutes plus 30-60 minutes soaking (optional)
Cook: 15 minutes
Prep: 15 minutes plus 3 hours freezing
Prep: 10 minutes plus 2 hours or overnight marinating
Cook: 15 minutes