Preheat oven to 425˚F. Spray a 12-cup muffin pan with cooking spray - set aside.
Combine maple syrup and butter. Stir to combine. Add the walnuts and dates, stir together until well combined. Set aside
Combine flour, sugar, baking soda, baking powder, cinnamon and salt in a large bowl and stir well with a fork to combine.
Make a deep well in the center of the dry ingredients. Add mashed bananas, egg, butter and vanilla to the well and stir with a fork in the center of the bowl, breaking up the egg yolk and mixing the wet ingredients.
Using a rubber spatula or wooden spoon stir wet and dry ingredients together until the flour mixture is incorporated. Don’t overmix.
Divide batter into prepared pan. Muffin cups should be about ⅔ full. Sprinkle topping mixture over the batter in the muffin pans, dividing evenly.
Bake muffins for 5 minutes, then reduce temperature to 350˚F. and continue baking for another 12-15 minutes or until tops are golden and muffin tops spring back when touched lightly on the top.
Cool muffins for 5 minutes in the pan then transfer to a cooling rack.
See Café Tips for more detailed instructions and tips.