1. Preheat oven to 350°F and line a 24-cup mini muffin pan with paper liners or coat with cooking spray.

2. In a large bowl, whisk flour, oats, sugar, cinnamon, baking powder, baking soda, salt and lemon zest; set aside.

3. Place beaten eggs in a medium bowl. Add melted butter, milk and vanilla; whisk until blended. Make a well in the flour mixture, add wet ingredients and stir until just combined. Gently stir in ½ cup walnuts and blueberries. Fill each mini muffin cup with about 1 rounded tablespoon of batter. Sprinkle evenly with remaining ¼ cup walnuts.

4. Bake 15 minutes or until toothpick inserted into the center comes out clean. Do not overbake. Cool 5 minutes on wire rack, carefully remove from pan and cool completely on wire rack before storing in a sealed container. Enjoy within 2 days.