Begin by preheating your oven to 350°F (175°C). Grease an 8x8-inch baking dish with cooking spray or line it with parchment paper for easy removal later.
In a large mixing bowl, combine the cooked and cooled mashed sweet potato with the creamy almond butter until the mixture is smooth and well blended, ensuring there are no lumps.
Next, add in the unsweetened cocoa powder, pure maple syrup, pure vanilla extract, fine sea salt, and baking powder. Mix thoroughly until all ingredients are fully incorporated and the batter is smooth and glossy.
Gently fold in the semi-sweet chocolate chips, distributing them evenly throughout the batter for a delightful chocolatey texture.
Pour the brownie batter into the prepared baking dish, using a spatula to spread it evenly across the bottom.
Place the baking dish in the preheated oven and bake for 25-30 minutes. When done, a toothpick inserted in the center should come out mostly clean, with a few moist crumbs sticking to it. This indicates a fudgy texture.
Immediately upon removing the brownies from the oven, sprinkle the mini marshmallows evenly over the top, creating a fluffy layer of sweetness.
Return the brownies to the oven and bake for an additional 5-7 minutes, or until the marshmallows have puffed up and developed a light golden color.
Once they are ready, allow the brownies to cool in the pan for at least 15 minutes to set. Then, using a sharp knife, cut them into squares for serving.
Notes
Best served warm with vanilla ice cream and chocolate syrup.