Cook the Sweet Potatoes. Pierce each sweet potato several times with a fork. Microwave on high for 10-15 minutes, or until tender when pierced with a fork. Let cool slightly before handling. OR Preheat oven to 400°F (200°C). Wrap each sweet potato in foil and bake for 45-60 minutes, or until tender when pierced with a fork. Let cool slightly before handling.
Once cooled, peel and mash the sweet potatoes.
In a large bowl, whisk together the mashed sweet potato, peanut butter, cocoa powder, maple syrup, and baking soda until well combined.
Line an 8x8 or 9x9 baking pan with parchment paper.
Spread the sweet potato mixture evenly in the pan. Bake at 350°F (175°C) for 30 minutes, or until set.
Remove the brownies from the oven and immediately sprinkle with dairy-free chocolate chips. Let the chips sit for a few minutes to melt slightly.
Use a spatula to spread the melted chocolate evenly over the cookies.
Let the brownies cool completely in the pan before cutting into squares or bars.
Store in an airtight container in the refrigerator for up to 3 days.