Preheat your oven to 350°F (175°C).
Grease your 9-inch round cake pans with oil and line with parchment paper.
In a large mixing bowl, whisk together flour, sugar, salt, and baking soda.
In another bowl, mix water, oil, vinegar, and vanilla extract until blended.
Pour the wet ingredients into the dry ingredients and mix until just combined. Fold in vegan sprinkles if using.
Divide the batter evenly between the prepared cake pans and bake for 30-35 minutes.
Let the cakes cool in the pans for 10 minutes, then transfer to a cooling rack.
Beat together vegan butter and cream cheese, then gradually add powdered sugar until creamy.
Once cooled, frost the cake layers with the prepared frosting.
