Swedish kardemummabullar are soft, rich yeasted buns with an aromatic butter, sugar and cardamom filling. This recipe does require a bit of time commitment and willingness to roll, measure, cut and shape the buns. We think it’s worth it. Despite being rich with butter, milk and an egg yolk, the dough is remarkably easy to handle. It’s essential to use cardamom seeds that you have ground yourself. Preground cardamom doesn’t come close to having the same flavor, aroma or visual appeal. Be sure to purchase decorticated cardamom seeds—seeds that have been removed from the thick, fibrous pods—and grind them in a mortar with a pestle or pulse them in an electric spice grinder to a mix of powder and tiny flecks. For the dough’s first rise (the bulk fermentation), we use a 9-by-13-inch baking dish as the container. This allows the dough to cool more quickly once it’s in the refrigerator. It also makes the dough easy to roll into a rectangle for filling because it takes on the shape of the baking dish. If you wish to make the buns over the course of two days, the ideal stopping point is after putting the dough in the refrigerator; it can remain there for up to 24 hours before rolling, filling, shaping and baking. Leftover baked buns, if you have any, will keep for up to three days in an airtight container; they reheat well in a 350°F oven for 5 to 8 minutes.