Preheat oven to 350 degrees F. Line an 11 x 7 1/2-inch pan (brownie pan) with parchment paper.
Place the cake mix in a medium size mixing bowl. Add the oil and 1 egg. Stir the mixture together with a fork until combined and mixture is still crumbly. Save 3/4 cup of the mixture for later use. Press the remaining mixture into the pan.
Bake for 9 minutes then remove from the oven.
Place the cream cheese, sugar, lemon juice, and the 1 remaining egg into a large mixing bowl. Beat ingredients together, using an electric mixer, until well combined and smooth.
Spread cream cheese mixture over the crust. Crumble the reserved topping and drop evenly over top of the cream cheese.
Bake for 14-18 minutes, or until cream cheese is set and top crust is light golden brown. Remove from the oven.
Set pan on a wire cooling rack and cool for about 30 minutes. Remove the cake bars from the pan by picking up the parchment paper on the side, set on a cutting board.
Allow bars to cool about 2 hours. Cut into the size bars desired. Yields 24 (1 1/2-inch bars). Refrigerate bars prior to serving.