Preheat your oven to 350°F (180°C). Line a 9×5-inch loaf pan with parchment paper or a paper liner and lightly oil it with cooking spray to ensure the bread won't stick. This simple step makes it so much easier to remove the loaf later—I never skip lining and oiling for quick breads!
Peel the ripe bananas and mash them thoroughly with a fork. Measure out 1 cup of the mashed banana for the recipe to ensure the correct texture and flavor in your bread.
In a large mixing bowl, combine the mashed bananas (from Step 2), pureed pumpkin, olive oil, date sugar or coconut sugar, and vanilla extract. Whisk these ingredients together until the mixture is smooth and evenly blended.
In a separate bowl, whisk together the all-purpose einkorn flour, pumpkin pie spice blend, baking soda, baking powder, and Celtic sea salt. Make sure the mixture is well combined to evenly distribute the leavening agents and spices. I find whisking rather than stirring helps prevent lumps of baking soda or flour.
Gently add the dry ingredients (from Step 4) into the bowl with the wet ingredients (from Step 3). Stir just until everything is combined—avoid overmixing, as this can cause the bread to turn out gummy rather than tender.
Pour the batter evenly into the prepared loaf pan (from Step 1). Place the pan on the center rack of your preheated oven and bake for 40–45 minutes, or until a toothpick inserted into the center comes out clean. Once baked, immediately transfer the pan to a wire rack to cool. For a moister crumb, I sometimes let the bread rest in the pan for just 5 minutes before removing it to finish cooling.