Preheat the oven to 350°F (180°C). Butter a 9 x 5 inch (23 x 13cm) loaf pan and line with parchment paper.

In a bowl (by hand or with a stand mixer), beat butter and sugar together until light and fluffy.

Add the eggs, one at a time, and then beat in the pumpkin puree, bananas, and vanilla. Scrape down the sides of the bowl to ensure even mixing.

In a small bowl, whisk together flour, pie spice, baking powder, baking soda, and salt.

Gradually stir flour mixture into the wet ingredients until just combined.

Pour the batter into the prepared pan and spread to even out.

Bake for about 60-75 minutes, until a toothpick inserted into the center, comes out clean.

Let cool in the pan for 10 minutes before inverting onto a wire rack to cool completely.

Store any leftovers in an airtight container, either at room temperature or in the refrigerator for up to three days. You can also freeze this bread in an airtight container for up to two months. Defrost in its container at room temperature for a couple of hours.