1. Place the cumin seeds in a small, dry skillet over medium heat. Shake the skillet gently to move the seeds as they toast so they don't burn; continue until aromatic, about 5 minutes. Transfer seeds to a spice grinder, and grind to a fine powder.

2. Place the dates in the bowl of a food processor; process until finely chopped. Remove and discard any seeds to make 3 tablespoons tamarind concentrate. Add concentrate, ginger, and ground cumin to food processor. Add 2/3 cup plus 2 tablespoons boiling water, or enough to make the mixture a spreadable consistency. Process until smooth. Add the cayenne and salt; adjust to taste.