I made some to garnish the sweet potato soup but it’s an easy swap for anywhere sour cream is wanted. I’m tempted to call it the Killer App for baked potatoes. Don’t be a hater! I put about a 1/4 cup of buttermilk into a pint of heavy cream and left it out overnight. I read to use non-pasteurized cream for best results but my cream was ultra-pasteurized and it worked splendidly.