Lemon Creme Bars

Why I Love This Recipe
This is my version of a recipe that I found on the Betty Crocker website. I made it for my co-workers and 2 of them begged me for the recipe because they LOVED them!
Ingredients You'll Need
1/2 cup cold butter (1 stick)
1 pouch (1 lb 1.5 oz) sugar cookie mix
1 egg
1 can (14 oz) sweetened condensed milk (not evaporated)
1/3 cup lemon juice
Directions
Heat oven to 350°F. Spray bottom of 9 x 11-inch rectangular pan with cooking spray.
In large bowl, cut butter into cookie mix, using fork or pastry blender. Stir in egg until mixture is crumbly. Press a little more than half of cookie mixture into bottom of pan (if dough is too sticky, add a little bit of flour to your hands); bake 15 minutes.
For thicker bars, use an 8 x 8 or 9 x 9 pan.