Vegan Sweet Potato Chocolate Cake with Chocolate Frosting Jan 24, 2022 · Lightly coat an 8” x 8” brownie/cake pan or a 9” round cake pan with coconut or other oil, and fit the bottom of the pan with a small piece of parchment paper. In a blender (or using a handheld blender and a deep cup or vessel), puree the sweet potato, 1/2 cup of the water, maple syrup, balsamic vinegar, and vanilla extract until ...