Preheat oven to 350F. Line an 8x8 or 9x9-inch baking dish with parchment paper (or grease lightly with butter or oil).
In a large bowl, whisk together the oil, tahini or almond butter, maple syrup, egg, and vanilla until smooth. Stir in the grated beet or sweet potato.
Add the almond flour, cocoa powder, coconut sugar, baking soda, and salt. Use a rubber spatula to mix until well combined. Stir in the chocolate chips. Transfer to your prepared baking dish and spread into an even layer.
Bake for 25-30 minutes, or until a knife or toothpick comes out clean-ish (melty chocolate chips will stick!).
Let cool for at least 10 minutes before removing and slicing. If you are slicing and serving straight for the pan, cut them with a knife, then use a big spoon to scoop the warm brownie out. They are also delicious cold!