The bun is traditionally a cardamom yeast bun. You carve out the insides and then blend the crumbs with almond paste and cream, filling the hole and then topping it off with whipped cream and then the little cap before dusting it in powdered sugar.
Admittedly, they are not as beautiful when I make them myself, but they still taste good! I like to add strawberry jam to mine. The bakeries here sell them in February. They even have a semla day!
This year someone thought to do a twist on the original and created the semla wrap. It was pretty great. A lot lighter than the classic bun. I’m not sure how common they were across Sweden this season, but we had them in Kiruna!
So, if you ever find yourself in Scandinavia in February, try a semla!