Preheat oven to 350 degrees. Spray a 9" x 13" baking dish with non-stick cooking spray.
In a large mixing bowl prepare cake batter per directions on back of cake mix box. Beat batter for 2 minutes for a fluffy cake.NOTE: For bakery style substitute milk for water, melted butter for oil, and 4 eggs for the 3 eggs.NOTE: cool melted butter before adding to mixing bowl. This will prevent eggs from scrambling. Pour cake batter into prepared baking dish and spread evenly. Dollop all of the lemon pie filling all over the cake batter. Using a knife swirl the pie filling into the cake batter.NOTE: Do not over swirl. You do not want to combine them together, just swirl around. Bake in preheated oven until done. Use a toothpick to insert into the cake part and it comes out clean. Cake should have pulled away from dish. Remove from oven and allow to cool in baking dish before next step.
Once cake has cooled, Place cream cheese frosting into a medium mixing bowl. Using an electric hand mixer beat for a few minutes until fluffy. Add in lemon extract and mix until combined. While beating the frosting add thawed cool whip a little at a time until it's all combined.
Spoon mixture over cooled cake and spread evenly.
Cut lemon slices 3/4 of the way through slice and twist the lemon slice. Place the twisted lemon slices on cake evenly.
Refrigerate for 1 hour to set up. Ready to serve. Left over cake should be refrigerated.
Since you’re using a box cake mix, I don’t understand why you wouldn’t just go ahead and use a lemon cake mix instead of a vanilla cake mix. In my mind, the more lemon flavor the better.
Because we don’t like the lemon flavor in the lemon cake mix, we find it too artificial.
Can these be made into cup cakes? Definitely want to make this.
I’ve never tried doing that, but if you do let me know how it turns out.