1drop pink food coloring geloptional (see recipe note)
Preheat oven to 350 degrees F. Coat a 13- x 9-inch glass baking dish with nonstick cooking spray. Set aside.
Sift the flour together with the cornstarch into a large medium mixing bowl. Add strawberry jello, baking soda, and salt. Stir until well combined. Set aside.
Using an electric mixer, beat softened butter and sugar together in a large mixing bowl until light and fluffy. Add eggs, one at a time, beating until blended after each addition. Beat in lemon juice and vanilla.
Add the flour mixture to the butter mixture, in increments, alternating with the buttermilk. Beat on low in between additions, until all of both have been added. Beat just until combined. Use a spoon to gently stir in chopped fresh strawberries.
Transfer cake batter to the prepared baking dish.
Bake in preheated oven for 35 to 40 minutes or until a wooden pick inserted in center comes out clean. Cool completely (about 1 hour). Spread with Strawberry Cream Cheese Frosting.
Strawberry Cream Cheese Frosting
Beat cream cheese and ⅓ cup sugar with an electric mixer until smooth. Set aside
Beat heavy cream and lemon juice at medium speed until foamy; increase speed to medium-high, and slowly add remaining ⅓ cup sugar, beating until stiff peaks form. Fold whipped cream mixture into cream cheese mixture with a spoon. Add strawberries and stir, just until combined.
To tint the frosting pink, add 1 drop of pink food coloring gel to the cream cheese and sugar mixture and beat until completely incorporated. Continue with recipe as directed.