Preparation

Line a large colander with coffee filters, cheesecloth, or paper towels, and set it over a deep plate or bowl. Pour in the yogurt and refrigerate overnight or up to 12 hours. (The whey will drain out, making the yogurt thick and creamy).

In a mortar and pestle, crush 1/4 tsp. saffron threads into a powder. In a large bowl, combine the yogurt, crushed saffron, sugar, salt, and cardamom. Mix until the yogurt turns pale yellow. Top with the remaining 1/4 tsp. saffron threads and the pistachios. Refrigerate for at least 2 hours or up to 8 hours before serving.