Preheat oven to 350°F (175°C). Grease and flour a 9x13 inch baking pan.
In a large bowl, combine cake mix, strawberries, oil, and eggs. Beat until well combined.
Pour batter into prepared pan and bake for 30-35 minutes, or until a wooden skewer inserted into the center comes out clean.
Let cake cool completely before frosting.
For the frosting, beat cream cheese and butter together until smooth. Gradually add powdered sugar and vanilla extract, beating until light and fluffy.
Frost the cooled cake and decorate with fresh strawberries, if desired.
Notes
For a richer flavor, try adding a tablespoon of strawberry extract to the batter. You can also substitute the fresh strawberries with frozen, but be sure to thaw them first.