In a small sauce pan heat the milk, saffron, 1/4 cup of the sugar and butter together until the butter melts, but do not boil the milk, it just needs to be warm. Add the yeast to the warm milk and let it sit a bit so that the yeast dissolves. You don't want the milk too warm because it will kill the yeast.
In the bowl of your mixer, mix the flour, salt, cardamom, remaining 1/ cup sugar and salt.
Add milk mixture, 2 eggs and sour cream to the flour mixture and using the hook attachment mix well until dough is smooth. Add raisins and mix until raisins are evenly distributed in the dough.
Place the dough in an oiled bowl, cover with plastic wrap and place in a warm spot until it doubles in size.
Preheat oven to 400 F degrees. Prepare a baking sheet with parchment paper.
Sprinkle some flour over your counter and turn the on the counter. Divide into 12 pieces. Roll each piece into a rope about 8 inches long and shape them into the letter "S".
Place the rolls on the baking sheet, cover with plastic wrap and let them rest for another 30 minutes until they have doubled in size. Brush the buns with egg wash. Place a single raisin in the center of each of the swirls.
Bake for about 10-12 minutes or until golden brown.