In stand mixer or mixing bowl, mix banana, butternut squash, eggs, applesauce, sugar, and oil, until well blended.
In separate mixing bowl, combine salt, baking soda, baking powder, cinnamon, wheat flour and white flour.
Add the dry ingredients into the wet ingredients and mix until batter forms.
Pour into greased baking cups or muffin tins, and sprinkle with brown sugar-cinnamon topping.
Bake at 350. Regular size muffins for 16-18 minutes. Mini muffins for 13-15 minutes.