Preheat the oven to 350 degrees F and grease an 8x8-inch pan with nonstick spray.
Add the chickpeas to a colander to drain. Rinse with water. Drain.
Add to a food processor with the banana, peanut butter, maple syrup, vanilla, salt, and baking soda. Grind on high to make a uniformly smooth batter. (It might take 15-30 seconds.)
Pulse in the flour and chocolate until just combined.
Pour batter into the prepared pan and bake for 24-26 minutes, or until the edges are lightly golden brown and the top is firm to the touch.
Let cool fully in the pan and slice to serve.
Notes
Store leftovers in an airtight container in the fridge for up to 5 days. I prefer them chilled, but they are fine at any temperature.
Be sure to use a very ripe banana for the best flavor.
These are not super sweet. Add 2-4 tablespoons sugar to the batter if desired.
Use honey instead of maple syrup if needed.
Use almond butter or sunflower seed butter instead of the peanut butter.
Use a gluten-free cup for cup flour blend instead of all purpose if desired.