Pre-heat oven to 350 degrees and prepare muffin tins with paper liners.
Sift together all of the dry ingredients in a bowl: Flour, baking soda, baking powder, cinnamon, nutmeg, allspice and salt.
In a large bowl, cream together the sugars, vanilla, and eggs. Add in the sour cream, mashed bananas with the pumpkin puree and stir to combine.
Fold in the dry ingredients to the wet ingredient mixture until just combined.
Spoon batter into lined muffin tins until ¾ full. Bake for 20-22 minutes, until golden brown. Let them cool on a wire rack before serving or storing.