4 pounds lamb bones and trim
1 pound mirepoix (1 part carrot, 1 part celery, 2 parts onion) OPTIONAL
Water to cover
In 400F oven roast the bones (and mirepoix, if using) in roasting pan for about 30-40 minutes until they are will browned. Add water and cover bones. Bring to simmer on stove for 2-3 hours, skimming the impurities (in the form of foam) as it floats to top. When flavor is extracted, strain bones and vegetables out of liquid. Reduce liquid by half. Chill quickly until needed to use.