In a small pot, gently heat the cream, butter, and salt until the butter has melted and the salt has completely dissolved.

Remove from heat and add the vanilla.

In a larger pot, combine the sugar, corn syrup, and water.

Heat over a medium high flame, swirling the pot occasionally to distribute the heat evenly.

Continue to boil the sugar mixture until the bubbles begin to get smaller and it becomes amber-colored.

Reduce the heat to low, and pour in the warm cream mixture, whisking constantly to avoid lumps or crystals.

Immediately transfer the hot mixture to a heat-safe vessel and cool completely.

Preheat the oven to 325 degrees F, and mist a 9 by 13-inch pan with non-stick spray. Line with parchment.

Place the sugar, butter, and cocoa in a large microwave-safe bowl, and microwave* in one-minute increments, stirring, until the butter is completely melted and the mixture feels very warm to the touch.

Add the eggs, one at a time, stirring after each addition.

Stir in the vanilla.

Stir in the flour, baking powder, and salt.

Transfer half the batter to the pan, then drizzle with about 1/3 of the salted caramel. 

Top with remaining brownie batter, and swirl about 1/3 of the salted caramel mixture on top. 

Bake for 45-60 minutes, or until set around the edges but still soft towards the middle.

Cool completely in the pan, then transfer to a cutting board and cut into squares.

Drizzle with remaining caramel and garnish with sea salt.