Preheat the oven to 350℉. Line an 8” x 8” baking dish with parchment paper.
While the oven is preheating, mix together the ground flaxseed and water. Set aside for 5 minutes to gel to create the flax egg.
Drain, rinse, and dry the chickpeas. Then, to a food processor, add the chickpeas, peanut butter, maple syrup, vanilla, and flax egg. Bend until the mixture is as smooth as possible, stopping to scrape down the sides as needed. Next, add in the all-purpose flour, almond flour, baking powder, salt, and cinnamon. Blend again until the mixture is smooth.
Transfer the chickpea mix to a mixing bowl and add in the flaxseed and dark chocolate. Mix well until everything is evenly distributed.
Transfer the batter to the lined baking dish and bake for 25 to 28 minutes. Once pulled out of the oven, top with an optional pinch of flaky sea salt. Let the blondies cool completely before slicing.
Storage Instructions: Store the blondies in an airtight container at room temperature for up to 2 days, in the refrigerator for up to a week, or in the freezer for up to 3 months. They stay incredibly moist when chilled, making them a perfect "grab-and-go" snack from the fridge.