Preheat your oven to 420F (215C). Prepare two 12-cup muffin pans by placing 6 liners in each pan.
Combine flour, baking soda, baking powder, pumpkin spice,and ground cinnamon, in a medium bowl. Stir these together until they're well mixed.2 cups All purpose flour , 1 tsp baking soda, 1 tsp baking powder, 2 tsp pumpkin pie spice, 1 tsp ground cinnamon
In a large mixing bowl, whisk melted butter, oil and brown sugar. When the sugar is dissolved, add the eggs and whisk them to the mixture, followed by salt, and vanilla extract.1/4 cup oil*, 1/4 cup melted butter, 2 large eggs, 2 large eggs, ½ tsp salt
Add your pumpkin puree and mashed banana to your wet ingredient mixture. Continue to beat the mixture until the pumpkin is fully incorporated.1 cup pumpkin puree*, 1 cup banana
Pour your dry ingredients into your wet ingredients, and whisk them together until they're fully combined. Don't overbeat.
Divide your pumpkin batter evenly among the 12 muffin cups using a tablespoon or an ice cream scoop.
For the streusel topping, mix the flour, brown sugar and pecans. Cut the cold butter into the mix until it's crumbly.¼ cup all purpose flour,⅓ cup brown sugar,⅓ cup pecans,¼ cup butter
Sprinkle the topping evenly on the batter.
Place both muffin pans in the oven and bake at 420F for 5 minutes and reduce the temperature to 375F and bake for 13 to 15 minutes until a tootthpick inserted in the middle comes out clean.
Allow your muffins to cool in the pan for a few moments, then transfer them to a wire rack to cool completely.
Notes
Oil: use vegetable oil, sunflower oil, canola oil, avocado oil, or light olive oil.Pumpkin: use canned pumpkin puree for consistent results.Notes:
Make sure all the ingredients are at room temperature for easier mixing.
Don't overbeat.
make sure your baking soda and baking powder are fresh.
Storage: Can be stored on the counter in an airtight container for 3 days. Transfer it to a refrigerator if keeping for longer.Freeze: Transfer to a freezer bag and freeze for 3 months. Thaw overnight in the fridge or reheat gently in the microwave.