Preheat oven, 350 degrees.
In a mixing bowl, add lemon cake mix, 2 eggs, and melted butter. Use a fork to mix until dough forms. Press into a greased 9x13-inch pan (I love my glass pyrex pan). Set aside.
In a clean mixing bowl, blend cream cheese and lemon frosting together. Split mixture into 2 parts. (1/2 will be used in the cheesecake filling and the other 1/2 will be used as the lemon cream cheese frosting).
To make the cheesecake filling, take a bowl with 1/2 of the cream cheese mixture and add 2 eggs and vanilla. Beat until blended. Spread evenly over crust.
Bake at 350 degrees for 38-42 minutes until set. A toothpick poked into the center should come out clean when it's done. Cool completely before frosting.
Using the remaining 1/2 of the cream cheese mixture, frost bars. Cut into 20-24 pieces and enjoy!