Preheat oven to 400°. Spray twelve muffin cups with nonstick cooking spray.
Whisk flour, baking powder, baking soda and salt together in a medium bowl; set aside. In a large bowl whisk eggs until frothy, slowly whisk in sugar, then applesauce, then vanilla. Add half the flour mixture, then half the sour cream, then the other half of the flour mixture then the other half of the sour cream combining after each addition. Gently fold in blueberries.
Divide between muffin cups and bake until light golden and a toothpick inserted into the center comes out clean, 18 -20 minutes. Cool 5 minutes then transfer to a wire rack to cool.
Notes
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