Melt the butter on the stove, and add milk. Add saffron, and set it to the side. Make sure that the mixture is slightly warmer than body temperature.
Combine all-purpose flour, sugar, salt, cardamom, and instant yeast in a bowl. Add the milk mixture. Knead the dough by hand, or use a stand mixer if you have one, for 5-15 minutes, or until the dough forms a ball. You can add more flour if the dough feels too wet.
Cover the mixing bowl with a clean kitchen towel or plastic foil, and leave the dough to rise until it's doubled in size, about 30-40 minutes.
Sprinkle flour on a work top or table, and knead the dough thoroughly by hand to remove any air bubbles. It should not be very sticky.
Separate the dough into about 20 equally sized balls. Roll them individually into long strips, about as thick as a finger. Then roll the strips into any shape you like to form lussekatter. Use your imagination to create different shapes!
Place the lussekatter on a baking sheet covered with parchment paper. Leave a little space between each, as they will rise when they bake.
Preheat the oven to 480 F / 250 C. Meanwhile, leave the lussekatter to rest for a further 15 minutes covered by a clean kitchen towel.
Whisk the egg in a small bowl, and use a pastry brush to brush a thin layer of egg over each bun. Decorate with raisins.
Bake in the oven on the middle shelf for 5-7 minutes, or until they are golden on top. Remove from the oven, and leave them to cool down on a cooling rack.