Greek Yogurt (Best Option)
1:1 (1/4 cup Greek yogurt per 1/4 cup sour cream)Greek yogurt works well because it has a similar protein structure and acidity level as sour cream, which helps in binding the dry ingredients and adding moisture without making the granola soggy. The tangy flavor complements the natural sweetness of granola components.
For best results, use full-fat Greek yogurt to mimic the fat content of sour cream, which aids in texture and flavor. Avoid overly watery or low-fat versions as they can make the granola mixture too loose.
The final granola will have a slightly tangier note and a moist, cohesive texture close to the original recipe using sour cream, making it the most reliable substitute.