200 ml milk, 50 g yeast, 100 soft butter, 2 eggs, 1/2 tsp cardamom, 2 tbsp sugar, 1/2 tsp salt, 500 g flour
warm the milk and stir the yeast into it. Mix with the rest ingrediences. Let it proof for around 30 minutes.
filling: 150 g soft butter, 85 g sugar(100 ml), 2-3 tbsp cinnamon
Mix the sugar, butter and cinnamon.
knead the dough and split it into 2 parts. Roll each part out into a rectangle (ca. 25x40 cm), and spread the filling on it.
Roll them up from the long side to roulade and cut each into 15 pieces. Put them on a greased baking-plate and bend the endpieces of each bun under the bun. Let the rolls proof for 30 minutes. Brush them with a mixed egg and bake them in the middle of the oven.
10 minutes at 225°C
I just found a swedish page- http://www.recepten.se/recept/kanelbull
Their filling is a bit different: 50 g butter, 50 ml sugar and 1 tsp cinnamon and they say you can replace the cinnamon in the filling with cardomom or vanilla sugar.
And another good filling would be: 50 g butter, 2oo g raspberry and 200 g shredded almonds!