Preparation
Set aside 2 tablespoons of butter.
Preheat oven to 350°F. Line a 9×13-inch baking dish with parchment paper.
In a large bowl, beat sugar and 1 ¾ sticks butter until fluffy. Slowly add cocoa powder and flour and mix until well incorporated.
Transfer batter to baking dish. Press to spread around baking dish. Bake for 15 minutes.
In a medium saucepan on low heat, melt 2 tablespoons butter with sweetened condensed milk. Stir until thickened, remove from heat and add vanilla. Pour sauce over top of baked crust. Return to oven and bake until golden brown, 8-10 minutes.
Toast nuts in a dry pan until fragrant. Cool slightly then rough chop and set aside.
Melt caramel chips in microwave with 4 tablespoons heavy cream; 30 second intervals, stirring each time, for 2 minutes. Fold nuts and salt into caramel sauce, and pour over top and spread out to edges. Cool completely before cutting into bars.
