Preheat the oven to 350℉. Spray three 8-inch cake pans with baking nonstick spray. Line the bottoms with parchment paper circles and spray again.
In a medium bowl, sift the flour, baking powder, baking soda, and salt. Set aside.
3 1/2 cups All-purpose flour, 2 tsp Baking powder, 1/2 tsp Baking soda, 1 tsp Salt
Using a mixer, beat the butter, oil, and sugar on high speed for 2 minutes. Scrape the bowl using a baking rubber spatula.
1 cup Unsalted butter, 3 TBSP Oil, 1 3/4 cup White granulated sugar
Add the vanilla, sour cream, and eggs. Mix on medium until combined. Scrape the bowl. Add the dry ingredients and buttermilk. Mix on low speed until just combined.
1 tsp Pure vanilla extract, 3/4 cup Sour cream, 4 Large eggs, 1 cup Buttermilk
Remove from the mixer and add the peppermint chips. Mix until combined.
1 cup Andes peppermint chips
Pour the batter and spread evenly between the three cake pans. Bake for 27-30 minutes. Bake until a toothpick inserted comes out clean.
Let the cakes sit in the hot pans for 10 minutes. Transfer to a cooling rack. Cool completely before decorating.