Preheat oven to 350°F and line a 9x13-inch baking dish with parchment paper.
Beat 1 ¾ sticks of butter and sugar until fluffy.
Mix in cocoa powder and flour.
Press batter into the dish and bake for 15 minutes.
Melt 2 tablespoons of butter and sweetened condensed milk in a saucepan until thickened; add vanilla.
Pour over the baked crust and bake 8-10 minutes.
Toast nuts, chop, and set aside.
Melt caramel chips with 4 tablespoons of heavy cream in the microwave.
Fold in nuts and salt, then pour over the bars.
Cool completely before cutting.
