This traditional Scandinavian yeast bread is time-consuming to make, but it looks as good as it tastes.
Scald the 1-½ cups milk and cool to lukewarm. Crumble the yeast into a bowl and add 1 tablespoon of the sugar and the lukewarm milk. Beat in 3 cups of the flour with an electric mixer, beating until smooth. Cover and let rise until light and doubled in bulk, 1 to 1-½ hours.
Add the butter, remaining sugar, egg yolks and egg, cardamom, and salt and mix in. Gradually add 3 cups flour. Pour ¼ cup flour on a board, turn out the dough, and knead until smooth and elastic. Use only as much more flour as needed to keep the bread from sticking.
Place the dough in a greased bowl. Cover and let rise until doubled in bulk, 1 to 1-½ hours.
Cut risen dough in half for 2 braids. Cut each half into 3 pieces. Roll each piece into a rope 16 inches long. Pinch the 3 ropes together at one end. Braid ropes and pinch other ends together. Place on a greased baking sheet. Make second braid and place on second baking sheet.
Let braids rise until doubled in bulk, about 45 minutes. Preheat the oven to 350 degrees F. Before placing breads in oven, brush each with 1 tablespoon milk and sprinkle with 3 tablespoons sugar. Bake for 30 minutes, until golden brown.