Grind Saffron with 1 tsp of sugar in a mortar & pestle.
Heat milk in a small pot with the saffron-sugar mix over low-medium heat until steaming, and the saffron dyes the milk.
Allow the mixture to cool slightly till it is warm.Stir in the yeast and set aside until foamy, around 10 minutes.Add the remaining wet ingredients butter, egg, yogurt and vanilla to the yeast-milk mixture. In a bowl, add flour, sugar, baking powder and salt.
Make a well in the center and add the wet ingredients.
Mix the ingredients until well incorporated.
Turn the dough out onto a lightly floured countertop and knead, adding more flour as needed to keep the dough from sticking to your hands. Shape it into a ball and place it in a bowl in a warm place for around an hour till it doubles in size.
When the dough is ready, divide it into 6 parts, and shape each into a ball. Shape each ball into a snake. Then curl the ends in opposite directions till you form desired S shape.
Place the buns on a parchment paper. Place one raisin in each spiral. Using a pastry brush, brush the buns with the beaten egg.Leave the buns in a warm place again for around 20minutes. Preheat oven to 200°C.Bake the buns for around 10minutes till golden.Leave to cool and enjoy!