Preheat the oven to 350°F. Line the bottom of two 8" cake pans with parchment paper.
In a large bowl, whisk together the flour, sugar, cocoa powder, baking soda, and salt.
Add the soy milk, beet juice, melted butter, vanilla, and apple cider vinegar. Mix until just combined.
Divide the batter into the prepared pans.
Bake for 35-40 minutes, until the center of the cake feels firm and a toothpick comes out clean. Let cool completely on a wire rack. For best results, refrigerate overnight after cooling.
Make the Vegan Cream Cheese Buttercream Frosting. Place in the fridge until ready to frost. Use a serrated knife to level the cakes. Reserve some cake crumbs for decorating, if desired.
Invert the first cake onto a plate or cake stand. Add a layer of frosting, then add the other cake.
Use an offset spatula to spread a very thin layer of frosting all over the cake. This is a crumb coat. This covers the cake in frosting, allowing for a smoother final coat. Refrigerate for 1-2 hours to set the frosting.If you do not want to crumb coat, feel free to just frost the entire cake at this step. After the cake is chilled, use an offset spatula to cover the cake with the remaining frosting.
Sprinkle cake crumbs in a circle around the top edges of the cake to decorate.Serve! Keep any leftovers refrigerated.