1. Prepare the sweet potato: Cook the sweet potato by baking, steaming, or microwaving until very soft. Remove the skin and mash the flesh in a bowl until completely smooth with no lumps. Measure out 1 cup of mashed sweet potato and let it cool slightly.

2. Mix the wet ingredients: In a mixing bowl, combine the mashed sweet potato, almond butter or peanut butter, maple syrup, and vanilla extract. Stir until the mixture is creamy, thick, and well combined. This forms the rich base of your brownies.

3. Add the dry ingredients: Add the cocoa powder, oat flour or almond flour, baking powder, and salt to the bowl. Gently fold everything together until no dry spots remain. The batter will be thick and fudgy, not runny.

4. Fold in the chocolate chips: Add the vegan chocolate chips and fold them evenly through the batter so every brownie square gets melty chocolate pieces in each bite.

5. Prepare the pan: Line an 8x8 inch baking pan with parchment paper, leaving some overhang on the sides for easy removal. Spread the brownie batter into the pan and smooth the top with a spatula.

6. Bake the brownies: Bake in a preheated oven at 350°F (175°C) for 22–28 minutes. The edges should look set while the center remains slightly soft and fudgy. Avoid overbaking for the best texture.

7. Cool, chill, and slice: Let the brownies cool completely in the pan, then chill in the refrigerator for at least 30 minutes for maximum fudginess. Lift them out using the parchment, slice into squares, and enjoy.