Sourdough Vanilla Cake

• Preheat the oven to 350 degrees F and line two 9-inch cake pans with butter and parchment paper.

DRY INGREDIENTS

• In a medium mixing bowl, whisk together the cake flour, baking powder, and salt. Set to the side.
• 290 grams cake flour *see notes,9 grams baking powder,5 grams salt

WET INGREDIENTS

• In a liquid measuring cup, whisk together the room-temperature milk and sourdough starter discard until smooth. Set aside.
• You can use active sourdough starter instead of sourdough discard, just be sure to use the same amount in grams.
• 240 grams milk, room temperature,120 grams sourdough discard, room temperature
• In the bowl of a stand mixer with a paddle attachment or in a large mixing bowl with a hand mixer, beat the sugar and soft room temperature butter at medium speed for about 3-4 minutes, or until light and fluffy and white in color. Scrape down the sides of the bowl, when needed. Do not rush this step. Creaming the butter and sugar together is how we incorporate air in the batter so that our cake will bake up light and fluffy. If your kitchen is on the cooler side, you might want to run your mixing bowl under warm water so the metal bowl isn't ice cold.
• 113 grams unsalted butter, room temperature,350 grams sugar
• Next, add in the eggs, one at a time, beating at medium speed until combined and a pale yellow color. Again, scrape the sides of the bowl when needed. Add the vanilla extract and oil and mix until incorporated.
• 170 grams eggs, room temperature,12 grams vanilla extract,15 grams oil

COMBINE

• While mixing on low, alternate between the dry ingredients and wet ingredients, starting with adding a third of the flour mixture to the butter mixture, then half of the discard mixture. Continue to alternate until everything has been added. Stop mixing when there are just a few streaks of flour left and finish by hand with a rubber spatula.
• LONG FERMENT: To long ferment, cover the just-mixed batter and place it into the fridge overnight. The following day, divide the batter evenly between two prepared cake pans and bake. You might need to add a few minutes to the bake time since the batter is chilled.
• Divide the cake batter evenly into the prepared cake pans.

BAKE

• Bake the Sourdough Vanilla Cake for 20-25 minutes. The cake is done when a toothpick comes out clean or with a few moist bites of cake.
• Remove the cakes from the oven and place on a wire rack to cool completely.

VANILLA BUTTERCREAM FROSTING

• In a stand mixer with a whisk attachment, beat the room-temperature butter at medium speed for 2-3 minutes, or until light and fluffy. Again, if you have a metal bowl, I suggest running the outside of the bowl under hot water and drying it before making the buttercream to help warm it up!
• 226 grams unsalted butter, room temperature
• Next, add the powdered sugar to the butter, one cup at a time at medium speed.
• 455 grams confectioners' sugar
• Finally, add the vanilla extract, heavy cream and a pinch of salt. Mix until combined.
• 12 grams vanilla extract,75 grams heavy cream,pinch of salt
• Assemble, decorate and enjoy!

Ingredients & Substitutions

Sourdough Vanilla Cake Ingredients:

• Flour: For the lightest and most tender sourdough discard vanilla cake, I highly recommend using cake flour. This flour is lower in gluten content, which creates a lighter and fluffier bake. However, you can substitute with all-purpose flour, but that may lead to a slightly denser cake.
• Unsalted butter: For the best cake texture, the temperature of your butter is important. Before creaming, the butter should be soft, so that a fingerprint can easily be left when pressed into the butter. If the butter is too hard or too soft, this will affect the texture of the cake. Aim for 67 degrees F. If you are using salted butter, subtract 1/4 teaspoon of salt from the recipe.
• Baking powder: Make sure your baking powder hasn’t expired, otherwise, the cake won’t rise properly. Refresh after 6 months of opening.
• Eggs: Bring eggs to room temperature quickly by placing them in a bowl of hot water for at least 5 minutes.
• Milk: I used whole milk for this recipe, however, you can substitute it with non-dairy options like almond milk. Bring the milk to room temperature quickly by heating it up for 15-20 seconds in a microwave-safe bowl.
• Unfed Sourdough Starter: I prefer using sourdough starter discard that is no older than 1-2 days for sweet recipes like this Sourdough Vanilla Cake.

Vanilla Buttercream

• Unsalted butter: Again, in order for the buttercream to be smooth, it is important that the butter is at room temperature before mixing.
• Powdered sugar: Add the powdered sugar one cup at a time while mixing to prevent sugar from flying everywhere!
• Vanilla extract: For the best vanilla flavor, use pure vanilla extract instead of imitation.

How to Decorate

• Before decorating, double-check that the cakes are completely cooled! If they are even slightly warm, the frosting will melt into a sugary mess.
• If the cakes are domed, slice off a thin piece of the top of the cake with a serrated knife to help level the cakes. This helps the cake to lay evenly when layered.
• First, place the bottom layer on the cake stand. Top with about a cup of the frosting and spread with an offset spatula or flat knife until it is evenly covered. Place the 2nd cake layer on top and cover evenly with another cup of frosting. Cover the edges with the remaining frosting.
• Leave the cake uncovered for at least 30 minutes to set. This makes for easier and cleaner slicing.
• I decorated my cake with frosting and these dye-free sprinkles, but here are some other creative ideas for you to try:
• Sprinkles
• Macaroons
• Edible Flowers
• Fresh Fruit