Put the cumin, coriander, cardamom, peppercorns, cinnamon, and cloves in a dry heavy skillet over medium-high heat. Toast the spices, stirring occasionally, until they turn several shades darker and give off a sweet smoky aroma, about 10 minutes. Do not raise the heat to quicken the process, or the spices will brown prematurely, leaving the insides undercooked. Cool completely.

Working in batches if necessary, transfer the mixture to a spice mill or coffee grinder and grind to a powder. Stir in the nutmeg and saffron. Use immediately or store in an airtight container in a cool, dry place.