- 2 cups heavy cream (pasteurized, not ultra-pasteurized if possible)
- 2 tablespoons cultured buttermilk or cultured full-fat plain yogurt
In a medium bowl, mix together the heavy cream and the buttermilk or yogurt. Stir to incorporate. Pour the mixture into a glass jar or plastic container.
Place in a warm room, partially covered, and let sit 12 to 24 hours, until thickened and slightly tangy. Chill and use for 7 to 10 days.