1 tablespoon freshly squeezed lemon juice
1/4 teaspoon saffron threads
10 medium whole cloves garlic
1 medium clove garlic, crushed
1 cup whole, low-fat or nonfat plain yogurt
1/2 teaspoon salt
1/4 teaspoon freshly ground black pepper
1/2 bunch tarragon leaves, washed and patted dry (1/4 cup)
Fill a small saucepan halfway with water, and bring to a boil over high heat. Add the whole cloves of garlic and cook for 5 minutes, until softened. Drain and let cool.
Place the lemon juice in a small glass bowl; add the saffron and let it sit for 5 minutes.
Transfer to the bowl of a food processor, along with the cooked and raw garlic, the yogurt, salt, pepper and tarragon. Process for 30 seconds to form a bright yellow sauce.
Transfer to an airtight container and refrigerate until ready to use (up to 2 days).
Serve with grilled meats and vegetables.
MAKE AHEAD: The sauce can be made up to 2 days in advance and refrigerated in an airtight container.