This quick bread makes good use of those bananas that are orphaned in your fruit bowl, slowly turning dark. Overripe bananas are perfect for banana bread, so don’t let them go to waste. The farro, spelt, and oat mixture adds intensity to the flavor of this banana bread, as do the buttermilk and cinnamon.
Mix the flours and buttermilk in a large bowl. Cover and let soak on the counter overnight.
In the morning, preheat the oven to 350°F. Grease a 10-by-5-inch loaf pan.
Use a fork to mash the butter in a medium bowl. Mash the bananas into the butter. Add the honey and eggs and mix well.
Combine the baking soda, cinnamon, and salt in a small bowl.
Add the banana mixture to the flour mixture. Stir until just combined. Add the baking soda mixture and stir briefly. Carefully fold in the nuts.
Pour the batter into the prepared pan. Bake for 40 minutes, reduce the temperature to 325°F, and bake until golden brown, about another 30 minutes. A toothpick should come out clean when inserted into the center of the loaf. Let cool completely before slicing and serving.