Preheat your oven to 400°F (200°C). Pierce a medium sweet potato several times with a fork. Bake for 45-60 minutes, or until very tender. Let cool slightly, then scoop out the flesh and mash it or blend it in a food processor until completely smooth. You'll need 1 cup of puree. Reduce oven temperature to 350°F (175°C).

Line an 8x8 inch (20x20 cm) baking pan with parchment paper, leaving an overhang on the sides to easily lift the brownies out later. Lightly grease if desired.

In a large mixing bowl, combine the sweet potato puree, plant-based milk, neutral oil, and vanilla extract. Whisk until smooth and well combined.

In a separate medium mixing bowl, whisk together the all-purpose flour, cocoa powder, granulated sugar, baking powder, and salt. Ensure there are no lumps of cocoa powder.

Gradually add the dry ingredients to the wet ingredients, mixing with a spatula until just combined. Be careful not to overmix; a few streaks of flour are okay.

Fold in 1/2 cup of vegan chocolate chips.

Pour the brownie batter into the prepared baking pan and spread evenly. If desired, sprinkle a few extra chocolate chips on top.

Bake for 25-30 minutes, or until a toothpick inserted into the center comes out with moist crumbs, but not wet batter. The edges should be set, but the center will still be a bit soft (this is for fudginess!).

Remove the pan from the oven and let the brownies cool completely in the pan on a wire rack for at least 1-2 hours before lifting them out using the parchment paper overhang. This is crucial for them to set properly and achieve a fudgy texture.

Once completely cooled, lift the brownies out of the pan, slice into 16 squares, and serve.