Can't Leave Alone Bars

Here is the final recipe from the progressive dinner. It's not nearly as impressive, but is fast and easy. I copied the recipe from somewhere, but neglected to write where; but once again credit goes to someone else.

1 pkg. white cake mix
2 eggs
1/3 C vegetable oil
1 can (14 oz) sweetened condensed milk
1 cup (6 oz) semisweet chocolate chips
1/4 C butter or margarine, cubed

1. In bowl, combine cake mix, eggs and oil. With floured hands, press 2/3 (I probably used about 3/4) of the mixture into greased 13x9 baking pan. Set remaining cake mixture aside.
2. In microwave safe bowl, combine condensed milk, chocolate chips, and butter. Microwave, uncovered for 45 seconds, stir. Microwave 45-60 seconds longer, or until melted. Stir until smooth and pour over cake mixture.
3. Drop teaspoons of remaining cake mixture over top. Bake at 350 for 20-25 minutes, or until lightly browned.