Preheat your oven to 350 degrees and spray a baking sheet (13x17 inches) with non-stick cooking spray.

In a large mixing bowl, cream the butter and brown sugar until it's well combined. Add the eggs and vanilla. Mix well. Add the salt and baking soda. Stir in the oatmeal. Finally, add the flour. Set the oatmeal dough aside .

For the filling, pour the chocolate chips in a 2 cup microwavable measuring cup. Put the 1 Tbs. butter, salt and vanilla on the top of the chocolate chips and pour the can of sweetened condensed milk over them. Microwave about 30 second at a time, stirring in between 30 second intervals until the chocolate is melted and everything blends together. Set to the side for a moment.

Using lightly floured fingers, press ¾ of the oatmeal dough into the bottom of your baking sheet. Pour the chocolaty filling on top and spread nearly to the edges of the pan. Take the remaining oatmeal dough and flattened it a chunk at a time with your hands and place the flattened pieces on top of the chocolate filling.

Bake for 25 minutes. When these bars are done they WILL NOT be lightly browned. You don't want to overcook them because then they will be dry instead of soft and chewy.

Cool completely before cutting. Cut up into 48 pieces and enjoy!