Healthy Flourless Pumpkin Gingerbread Blondies

mashed banana (approximately 1 large)

canned pumpkin

smooth almond or cashew butter (sub for another nut butter or sunflower seed butter to keep it allergen-friendly)

gingerbread spice (a mixture of nutmeg, allspice, cloves, cinnamon and ginger)

+ granulated sweetener of choice (optional)*