Combine the flour, oats, baking powder, baking soda, salt, cinnamon, nutmeg & cloves. Mix well. Set aside.
Combine the banana, sugars, butter, oil, yogurt, eggs & vanilla. Mix well.
Add the flour mixture to the banana mixture and mix until just combined.
Fold in the carrots and walnuts.
Fill greased or lined muffin tin with the batter.
For the topping, combine the walnuts, banana chips, butter, brown sugar and salt.
Sprinkle the topping evenly over the muffins.
Bake at 400 for 5 minutes, then reduce the heat to 350 and continue baking an additional 15-20 minutes.