Preheat oven to 350 degrees. Spray or oil the bottom only of two 8″ or one 9″ cake pan. Dust with flour and knock out excess.
In a large bowl, beat all cake ingredients with an electric mixer on low-speed for 30 seconds, until all ingredients are mixed together, stopping to scrape down. Turn mixer to high and beat an additional three minutes, scraping now and then.
Pour batter into prepared pan(s) and bake about 20 minutes if using an 8″ pan or 35 minutes if using a 9″ pan, or until a toothpick inserted in the center comes out clean.
Cool on rack 20 minutes, then remove cake and continue cooling.
To split cake horizontally in half, mark middle points around side of cake with toothpicks. Using toothpicks as a guide, cut through the cake with a long, sharp knife, using a back-and-forth motion