- Preheat oven to 350° and prepare 4 – 7” pans or 3 – 8” pans with spray release or grease and flour pans. Line pans with parchment.
- Place all dry ingredients in the bowl of a stand mixer. Using the paddle attachment, mix on low until ingredients are combined.
- With the mixer on low, add the chunks of butter. Mix until the mixture becomes crumbly and no large pieces of butter remain. Should resemble wet sand.
- Pour in egg whites and mix on low until just incorporated.
- Add in buttermilk in two installments, on low. Scrape the bowl between additions.
- Add vanilla and oil, mixing on low speed until fully incorporated. Scrape sides of bowl and beat an additional 15 seconds.
- Bake in preheated oven for 28-35 minutes or until a toothpick inserted in the center of the cakes comes out clean. A few crumbs are fine but if liquid is on the toothpick, return to oven.
- Let cool in pans for 10-12 minutes. Turn out onto cooling rack. When cakes are warm but cool enough to handle, wrap in plastic wrap and allow to finish cooling.
King Arthur is my go-to flour.
Make sure all your ingredients are at room temperature.
Bake your cake layers ahead and freeze them. They will last in the freezer for two months is properly wrapped. Wrap twice in saran wrap and once in heavy duty foil. To defrost, remove from freezer and allow to come to room temperature. Don’t unwrap the cake layer until they have defrosted.
No buttermilk? No problem. To make a substitute add 1 TBSP of either lemon juice or vinegar and add enough milk to measure 1 cup. Gently stir the mixture and let sit for 5-10 minutes.