1. Preheat oven to 350 dgrees. Lightly coat an 8 inch square baking pan with cooking spray. Line the pan with parchment paper, leaving a 3 inch overhang on two sides.
2. Using an electric mixer, beat the sugar and 6 tbsp. of the butter in a large bowl until light and fluffy, about 2 minutes. Reduce the mixer speed to low and gradually add the flour, mixing until fully inorporated. Using floured fingers, press the dough into the prepared pan. Bake until set and golden brown at the edges, 16 to 18 minutes.
3. Meanwhile in a medium saucepan combine the condensed milk, corn syrup, molasses, and 5 tablespoons butter. Stirring occasionally, bring to a simmer over mediu-low heat. Gently simmer, stirring until slightly thickened and pale golden brown, 5 to 7 minutes. Romove from the heat and whisk in the vanilla and salt. Immediately spread the mixture over the crust. Refrigerate until set, 30 to 45 minutes.
4. Place the chocolate and the remaining tbsp. butter in a microwave-saft bowl; cook on high until beginning to melt, 30 seconds. Stir until the mixture is melted and smooth. Spread over caramel and refrigerate until it is set. About 30 minutes. Cut into 1 inch squares.