In a large mixing bowl, dissolve the sugar and yeast in warm milk. Let the mixture stand for about 5 minutes, until foamy.
Combine flour and salt. Add the mixture gradually to the yeast mixture while stirring. Continue to stir until a dough forms and gathers at the center of the bowl.
Turn the dough over on a lightly floured board. Knead it until smooth for about 5 minutes or so. This dough is moderately stiff and not as elastic, a little bit drier than a regular bread dough. Shape it into a ball and place it in a bowl. Cover and let it rest for 10 minutes.
Roll the dough into a 12x8 inch rectangle. Dot dollops of softened butter in a single layer all over the dough. Fold the upper third of the dough over to the center, then fold the lower third up to create a business letter style fold. Wrap the dough in plastic and chill it in the freezer for 10 minutes.
Remove the dough from the freezer and unwrap. With the short edge close to you, roll it once more to a 12x8 inch rectangle. Fold it again business letter style. Wrap it in plastic and chill in the freezer for another ten minutes.
Finally, remove the dough from the freezer and unwrap it. With the short edge close to you, roll the dough into an 8x14 inch rectangle. Mix together fruit jam and butter and spread over the dough. In a small bowl mix together the cardamon, cinnamon, sugar and orange zest. Sprinkle all over the dough and press them lightly against the dough with a rolling pin o your hands.
Roll the long side of the dough towards the center to form a tight log up to the other side. Slice the dough into 12 equal portions. Place each portion on a greased 12-cup muffin pan. Cover the pan with plastic wrap and chill the dough overnight in the fridge.
In the morning, take the pan out from the fridge, let it rise for 45 minutes, or until puffy. Preheat oven to 375 F. Bake the buns at 375 F for 15-18 minutes or until lightly golden. Let cool slightly until easy to handle. Toss in sugar to coat. Serve warm.
You can also skip the overnight chill and go on with the process the same day. After placing the rolls in the pan, cover them with a clean kitchen towel. Let them rise at room temperature for 45 minutes, then bake.