Sour Cream (Best Option)
1:1 (1 cup sour cream per 1 cup Greek yogurt)Sour cream works well as a substitute because it has a similar fat content and acidity level to Greek yogurt, both of which are crucial for tenderizing the gluten in the flour and contributing to a flaky pie crust. The acidity also helps activate baking soda or other leavening agents if present.
When substituting, use the same volume of sour cream as Greek yogurt. Ensure the sour cream is full-fat or at least 18% fat for best results, as lower fat versions can affect dough texture. Avoid overmixing the dough to maintain flakiness.
The final crust will be very similar in tenderness and flavor, with a slight tang that complements savory or sweet pies. Sour cream may impart a marginally richer mouthfeel compared to Greek yogurt.