Heat oven to 400º. Spray 12 medium muffin cups, 2 1/2 × 1 1/4 inches, with
nonstick cooking spray, or line with paper baking cups. Toss blueberries
and all-purpose flour; set aside. Beat yogurt, oil, vanilla and egg in
large bowl. Stir in remaining ingredients just until moistened. Carefully
stir in blueberries.

Divide batter evenly among muffin cups (cups will be about two-thirds
full). Bake about 15 minutes or until golden. Immediately remove from pan
to wire rack. Serve warm if desired.