01 - Preheat the oven to 350°F. Line an 8x8-inch baking pan with parchment paper, leaving an overhang for easy removal.
02 - In a medium saucepan over medium heat, melt the sugar while stirring constantly until it turns amber. Add the butter and whisk until melted. Remove from heat, carefully whisk in the cream (it will bubble), then stir in the flaky sea salt. Allow to cool to room temperature.
03 - In a large bowl, whisk together melted butter, granulated sugar, and brown sugar until smooth. Add eggs and vanilla extract, mixing until glossy.
04 - Sift the flour, cocoa powder, and sea salt over the wet mixture. Fold gently until just combined. Stir in the chopped dark chocolate.
05 - Pour the brownie batter into the prepared pan and smooth the surface. Drizzle the cooled salted caramel over the batter, then swirl gently using a knife or skewer to create a marbled effect.
06 - Bake for 28 to 32 minutes, or until a toothpick inserted near the center comes out with a few moist crumbs attached.
07 - Allow the brownies to cool completely in the pan before lifting out using the parchment overhang. Cut into 12 squares and serve.