Preparation:
Preheat oven to 350 degrees.

Line a 9X13 baking pan with parchment paper and spray with cooking spray.

Cream butter, peanut butter, and both sugars in a medium bowl with an electric mixer. Add egg, vanilla, milk, salt and baking soda. Mix until combined. Slowly add flour and mix until dough comes together.

Press 2/3 of the dough in the bottom of the pan. The dough is very sticky so spray your hands with cooking spray first. Spread into a thin layer.

Sprinkle the chocolate chips on the top of the bottom layer. Pour the sweetened condensed milk over the chocolate chips. Try to give 1/2-inch border around the edges where the SCM does not touch the edge of the pan. This prevents bubbling edges.

Spoon tablespoon drops of your remaining dough over the top of the SCM layer. Flatten the dough with your fingers. It won't completely cover.

Bake for about 35-40 minutes, or until the bars begin to brown on top. Cool completely before slicing.