Preheat the oven to 350 degrees F (175 degrees C). Grease two 8-inch round cake pans and line with parchment paper.

Combine flour, baking powder, and salt in a bowl.

Cream butter and vanilla bean scrapings together in a large mixing bowl using an electric mixer at medium-high speed for 3 minutes. Scrape the sides of the bowl. Add sugar to mixture slowly. Scrape the sides of the bowl. Add eggs, 1 at a time, beating until well blended.

Mix buttermilk and vanilla extract together. Alternate adding flour mixture and buttermilk into butter mixture, beating on low speed until combined. Scrape the sides of the bowl and beat for an additional 20 seconds. Pour batter evenly into the prepared pans.

Bake in the preheated oven until cake is slightly brown on top, coming away from the sides of the pan, and a toothpick inserted into the center comes out mostly clean, 40 to 50 minutes. Let cool completely before frosting.