1cup (2 sticks)unsalted butter at room temperature
1 1/2teaspoonsvanilla extract
2cupsgranulated sugar
4large eggs
3/4cupbuttermilk
1(1-ounce)bottle red food coloring,2 tablespoons
Frosting
1(1-pound)box confectioners' sugar
2tablespoonsunsalted butter,at room temperature
1/2cupsour cream
1 1/2teaspoonsvanilla extract
Milkif needed, to thin frosting
Instructions
PreheatĀ oven to 350 degrees. Butter and flour, or spray with oil-and-flour baking spray, a 13x9x2-inch baking pan.
Sift both flours, cocoa powder, baking powder, baking soda, and salt onto a piece of wax paper. Set aside.
Using an electric mixer, cream butter and vanilla on high speed for 3 to 5 minutes. Stop mixer often to scrape down sides of bowl so that all butter is an even texture.
Turn mixer to low speed and add sugar in a slow and steady stream.
Once sugar has been added, turn mixer to high for 3 to 5 minutes, stopping frequently to scrape sides of bowl.
Beat in eggs one at a time.
Combine buttermilk and food coloring. With mixer on low-speed, add flour mixture, alternating with buttermilk mixture, beginning and ending with flour. Only beat long enough to combine ingredients and scrape down sides of bowl several times to make sure everything is evenly combined.
Pour batter into prepared pan and spread evenly with a spatula. Place in middle of oven and bake 40 to 45 minutes, until cake feels firm on top. Let cake cool completely before frosting.
For frosting, beat all ingredients (except milk) first at low-speed and then at high until light and fluffy. Thin with milk if too thick to spread. Spread on cake.