1 (30 oz.) low fat Ricotta cheese, 3/4 cup sugar (or Splenda), 1-1/4 cup liquid egg substitute (or 6 beaten eggs in a measuring cup that measures 1-1/4 cups), 1 box (20 oz.) Lemon cake mix, 1-1/3 cup water, 3 T. confectioner's sugar.
In a medium bowl combine Ricotta cheese, sugar (or Splenda), 3/4 cup eggs substitute (or 3 beaten eggs). Using electric mixer on medium speed beat smooth.
In a large bowl combine cake mix, water and remaining egg substitute (or 3 beaten eggs). Beat on low 30 seconds. Then beat on medium 2 minutes. Pour into a greased 13" x 9"pan. Spoon Ricotta mixture evenly over top of cake batter. Bake at 350 degrees for 60 - 65 minutes until edges are lightly browned and; center is only slightly wiggly. Cool until room temperature and place in frig for several hours before cutting. Before serving sprinkle confectioner's sugar evenly over top. Best if made a day ahead.