Followed the recipe exactly the first time and me and my mother really enjoyed it. She said it could use some heavy cream though, so the second time I used that instead of the sour cream. It's definitely better, but obviously adds much more fat. So it's up to you, either is good. I highly recommend chicken stock over vegetable stock for that savory addition. Veg stock gives it too much of a vegetable-soup taste. Instead of mashing it I took an immersion blender to the whole pot, just making sure to leave it a little chunky. It makes plenty so it's great for taking to work for lunch a couple of days.