In a medium saucepan over medium heat, melt the butter. Whisk in the milk, yeast and saffron and remove from the heat. Add in the sugar and combine.
Whisk in the 2 eggs and pour the mixture into a large bowl. Add in the flour and salt, and mix to form a sticky dough.
Turn it out onto a lightly floured surface and knead until smooth and elastic, about 5-10 minutes. Cover with a tea towel and let it rest for 45 minutes, or until doubled in size.
Divide the dough into 14 or so equal portions. Working with one piece of dough at a time, roll out into a strand, roll up one end into the middle, and roll the other end into the opposite side, forming an S-shape.
Place the buns on two large parchment-lined baking trays. Let the buns rest, covered with a tea towel, for another 15-20 minutes, until doubled.
Preheat the oven to 400°F / 200°C. Decorate the buns with raisins.
In a small bowl, whisk the egg for the egg wash and, using a soft-bristled brush, lightly brush the egg on top of the dough.
Bake the buns, one tray at a time, for 10-12 minutes, until golden.
