While the caramel is cooling, preheat oven to 350℉ degrees. Very lightly, butter an 8"x8" baking dish. Cut two 7"x 16" pieces of parchment paper. Place one piece in the dish with edges coming up the sides. Place the second sheet of parchment paper in dish coming up the other sides of the pan. Very lightly butter the parchment so all surfaces are lightly buttered. Set aside.
In a medium bowl or stand mixer bowl, stir together melted butter and the sugar until mixed well. Add eggs, vanilla extract, and salt, mixing on medium speed of the stand mixer or quickly by hand. Once combined fold in cocoa powder and flour.
12 Tbsp unsalted butter, 1 ½ cups sugar, 2 eggs, 2 tsp vanilla extract, ½ tsp salt, ¾ cup cocoa powder, ½ cup all-purpose flour
Pour about half the brownie batter into the baking dish, spreading evenly to the edges and up the sides of the pan a little.
Pour ½ cup (more or less, depending on your liking) of the salted caramel over the brownie batter, spreading evenly but not quite to the edges.
½ cup of the salted caramel
Spoon the rest of the brownie batter over the top, sealing in as much of the caramel as you can.
Bake at 350℉ degrees for 30 minutes. Then decrease temperature to 325℉ degrees and continue baking for an additional 10 minutes or until a knife inserted in the center comes out clean. Reducing the heat for the last few minutes helps the brownies to bake evenly from edges to center without the edges getting over-cooked.
Remove from oven and allow to cool completely (about 1 hour). Cut into 9 squares.
Serve with extra ½ cup caramel drizzled over each brownie, if desired. Also, sprinkle with coarse salt (just a little).
Coarse salt for sprinkling on finished brownies