Warm the milk until just steaming, stir in saffron, cover, and let steep 10 minutes. Cool to lukewarm.
Stir in the sugar, then sprinkle yeast over the warm saffron milk. Let stand until foamy, 5–10 minutes.
Whisk in the melted butter and 1 egg until the mixture is smooth and golden.
In a large bowl, combine flour and salt. Pour in the saffron mixture and mix until a shaggy dough forms.
Knead on a lightly floured surface (or mixer) until smooth and elastic, 8–10 minutes.
Place in a greased bowl, cover, and let rise in a warm spot until doubled, 60–90 minutes.
Line two baking sheets with parchment. Divide dough into 12 pieces. Roll each into a 10–12 inch rope and curl ends into an S shape. Press a raisin into each spiral.
Cover and proof until puffy, 30–45 minutes. Preheat oven to 400°F while they proof.
Beat the remaining egg with 1 tsp water. Brush buns and bake 12–14 minutes until deep golden. Cool on a rack before serving.