Preheat oven to 350°. Lightly grease an 8” x 8” pan. Stir water and eggs together until eggs are well blended. Add the lemon filling mix and stir until smooth. Set aside while crust is baking. Cut cold butter into crust mix. Blend until mixture resembles coarse crumbs. Press crust into bottom of pan. Bake 12 minutes or until slightly brown on top. Stir filling mixture again and pour over hot crust. Bake 22-26 minutes or until center does not jiggle when shaken and top begins to brown. Cool completely. Sprinkle powdered sugar over bars if desired. Cut into 16 lemon bars.