⭐ Sour Cream (Best Nut-Free Option)
1:1 (1 cup sour cream per 1 cup Greek yogurt)Sour cream is a fermented dairy product like Greek yogurt, containing similar fat content and acidity levels. This acidity helps activate baking soda, contributing to muffin rise and tender crumb. The thickness of sour cream closely mimics Greek yogurt, maintaining batter consistency.
When substituting, use the same volume and ensure sour cream is well mixed to avoid lumps. Because sour cream is slightly less tangy, muffins may have a milder flavor but remain moist and tender.
Overall, sour cream produces muffins nearly identical in texture and flavor to those made with Greek yogurt, making it the most reliable substitute.