Steep the saffron in 1/2 cup boiling water. In a skillet that can be tightly covered, melt the butter over medium-high heat. Stir in the rice and salt. Cook, stirring constantly, until the rice begins to absorb the butter and becomes opaque, but do not brown the rice. Quickly pour in the remaining 1 1/2 cups boiling water along with the saffron water. Cover immediately, reduce heat to low, and cook 20 minutes, or until all of the liquid is absorbed. For best results, do not remove the lid while the rice is cooking.
1/8 teaspoon powdered saffron
2 cups boiling water, divided
2 tablespoons butter
1 cup uncooked long-grain white rice, not rinsed
1 teaspoon salt