1 (18 1/4 ounce) packages
plain white cake mix
- Preheat oven to 350.
- Generously grease and flour a 13 x 9 inch baking pan.
- Place cake mix, sour cream, oil, eggs, and vanilla in mixing bowl.
- Blend with mixer on low speed for 1 minute.
- Stop machine, scrape down sides of bowl.
- Increase mixer speed to medium and beat 2 minutes more.
- Scrape down sides again if needed. The batter should look well combined and thickened.
- Pour the batter into the prepared pan.
- Place pan in oven.
- Bake the cake until it is light brown and springs back when lightly pressed with your finger, 35-40 minutes.
- Remove pan from oven and place on wire rack to cool for 20 minutes.
- Run a dinner knife around edge of cake and invert it onto wire rack.
- Allow cake to cool completely, 30 minutes.
- Frost as desired.