Rinse beans well to avoid any bean flavor., Peeling bean skins creates an even smoother batter but is optional., Do not overblend; stop once batter is smooth and even., Avoid overbaking; chilling completes the baking process and gives fudgy texture., Line pan with parchment paper for easier removal and cleaner slices., Using Dutch-process cocoa powder or adding espresso powder enhances chocolate flavor without coffee taste., Flour substitutions include oat, spelt, almond, or sorghum flour; for coconut flour reduce to 2 tablespoons due to moisture absorption., To make oil-free, replace milk with applesauce and omit oil, texture will be slightly different but still fudgy., Add mix-ins like chopped nuts or dried fruit, or swirl in nut butter before baking for variety., These brownies keep up to 5 days refrigerated, or freeze tightly wrapped for 2–3 months., Reheat by microwaving 10-15 seconds or enjoy at room temperature., Brownies taste better the next day after chilling., Using dried beans is possible by cooking them until tender and cooling before use., A high-powered blender can be substituted but may have slightly different texture than food processor.