Begin by adding your strawberries to a blender or food processor and blending. You will need 1 cup of pureed strawberries for the cake batter, plus an additional ¼ cup of pureed strawberries for the frosting.
Mix cake mix, eggs, and oil in a large bowl until well combined. Add JELL-O and 1 cup strawberry puree. Mix well.
Pour into a greased 9x13 pan.
Bake for 30 minutes.
Let the cake cool.
While the cake is cooling, make the frosting. Cream together the butter and cream cheese. Add vanilla, powdered sugar, and strawberry puree. Frost cake. ENJOY!