13-ouncepackage strawberry gelatin (not sugar-free or fat-free)
¼cupall-purpose flour
¼cup butter, softened and diced
¾cupvegetable oil
½cupbuttermilk, room temperature
4large eggs, room temperature
1teaspoonvanilla extract
Frosting:
1cupbutter, softened
3 ¾cupspowdered sugar
3tablespoonsmilk, room temperature
pinch ofsalt
½cupsliced strawberries, drained
Instructions
Cake
Preheat oven to 350 degrees F.
Add 1/4 cup granulated sugar to ½ cup sliced strawberries, undrained and allow to macerate for 30 minutes or longer.
Mix 1 15.25 ounces white cake mix, 1 3-ounce package strawberry gelatin (not sugar-free or fat-free), and ¼ cup all-purpose flour. Add ¼ cup butter, softened and diced and mix until blended. Pour in ¾ cup vegetable oil. Add ½ cup buttermilk, room temperature and mix until well combined. Add 4 large eggs, room temperature, one at a time, beating after each addition. Add 1 teaspoon vanilla extract and mix.
Stir in strawberries and any accumulated juice.
Bake in shallow 9x13 dish for about 30 minutes.
Frosting
Beat 1 cup butter, softened until light and creamy. Gradually add 3 ¾ cups powdered sugar. Add 3 tablespoons milk, room temperature and a pinch of salt. Gently stir in ½ cup sliced strawberries, drained until well-mixed.