I just wanted to add that I get ground cardamom from Spice Mountain. I have been making cardamom buns and cinnamon buns for many years and never liked grinding my own. When I had to grind it fresh, I found it too overpowering so reduced the quantity, or just infused the milk with lightly crushed cardamom pods for the dough, then ground cardamom for the filling.
Buns freeze really well, so I always make a batch (or a double batch) and freeze most. You can then defrost overnight as needed and then give them a short time in the oven for the 'freshly baked' taste.