Step 1 - Make the Vegan Buttermilk
Combine 2 cups of room temperature soy milk and 1 tablespoon of apple cider vinegar in a small bowl. Whisk together briefly and allow to sit for at least 10 minutes. The mixture will look slightly curdled by the end of the resting period this is correct.
Step 2 - Sift and Combine Dry Ingredients
In a medium bowl, sift together the flour, baking powder, baking soda, and salt. Whisk to combine evenly. Sifting removes lumps and ensures the baking powder and soda distribute evenly rather than sitting in concentrated pockets.
Step 3 - Cream Butter, Sugar, and Vanilla
In your stand mixer or large bowl with a hand mixer, cream together the room temperature vegan butter, granulated sugar, and vanilla extract on medium-high speed for 3–5 full minutes. The mixture should turn pale, fluffy, and significantly increased in volume.
Why does this extended creaming matter? Creaming incorporates air into the fat-sugar mixture this aerated mixture is what creates the light, tender, fine-crumbed texture of classic birthday cake. Insufficient creaming produces a denser, heavier cake that reads more like a coffee cake than a celebration cake.
Step 4 - Add Vegan Buttermilk
With the mixer running, slowly drizzle the soured soy milk into the creamed butter mixture. The gradual addition prevents the mixture from breaking adding all the liquid at once can cause the emulsion to collapse.
Step 5 - Add Flour Mixture Gradually
Add the sifted flour mixture a little bit at a time with the mixer running on low. Mix until just combined after each addition over-mixing at this stage develops gluten and produces a tough, chewy cake rather than the tender crumb you want.
The finished batter should be smooth, uniform, and pourable.
Step 6 - Bake the Layers
Divide the batter evenly among three greased and floured 8-inch cake pans. For genuine uniformity, weigh the batter using a kitchen scale even distribution produces layers that stack perfectly and bake in the same time.
Bake on the center rack at 350°F for 27–30 minutes until golden and a toothpick comes out clean. If your oven can't accommodate all three pans simultaneously, bake in batches.
Step 7 - Make the Frosting While Cakes Bake
Use an electric mixer to whip the room temperature Earth Balance vegan butter for 2 full minutes until completely smooth and lighter in color. Add the powdered sugar half a cup at a time, mixing on low after each addition until incorporated. Increase to medium-high and mix until the frosting comes together.
Add the 2 teaspoons of vanilla extract and whip on high for another 2 minutes until the frosting is fluffy and smooth.
Frosting consistency troubleshooting:
Too stiff- Add 1 tablespoon of plant-based milk at a time until spreadable
Too soft- Add powdered sugar ¼ cup at a time until it holds shape
Grainy texture- Continue whipping vegan butter-based frosting sometimes needs 5+ minutes of whipping to fully smooth
For colored frosting- Add gel food coloring (liquid coloring produces less vibrant colors and can affect frosting consistency) after the frosting reaches full development. Start with a small amount gel coloring is concentrated.
Step 8 - Level the Cakes
Once the cakes are completely cool (warm cake melts frosting and causes layers to slide), use a cake leveler or long serrated knife to trim any domed tops. Place each cake on a flat surface and cut horizontally at the lowest point of the dome, creating a flat top surface.
Leveling is IMO the step that separates home cakes from bakery-quality cakes. Even ½ inch of dome creates visible tilt in a 3-layer stack.
Step 9 - Stack and Frost
Place the first cake layer on your serving plate or cake board. Spread approximately ⅓ of the between-layer frosting (approximately 1 cup) evenly across the surface with your offset spatula. Place the second layer on top, press gently to adhere, and repeat. Add the third layer.
Apply a thin crumb coat a thin layer of frosting across the entire exterior and refrigerate for 20 minutes. The crumb coat traps any loose cake crumbs so your final frosting coat looks clean.
Apply the final exterior frosting coat, smoothing with the offset spatula. Decorate as desired.
