01 - Preheat oven to 175°C (350°F). Line a 23x23cm (9x9-inch) square baking pan with parchment paper, leaving an overhang on sides.
02 - Whisk melted butter, granulated sugar, and light brown sugar in a mixing bowl until well combined. Beat in eggs one at a time, then stir in vanilla extract.
03 - Sift together all-purpose flour, cocoa powder, and fine sea salt, then gently fold into the wet mixture until just incorporated. Do not overmix.
04 - Pour the batter into the prepared pan and spread evenly with a spatula.
05 - Combine caramel candies and heavy cream in a microwave-safe bowl. Heat in 30-second intervals, stirring until smooth and melted. Sprinkle flaky sea salt into the caramel.
06 - Drizzle melted caramel over brownie batter. Use a skewer or knife to swirl caramel throughout the surface.
07 - Scatter mini pretzels and semi-sweet chocolate chips evenly on top.
08 - Transfer pan to oven and bake for 30–35 minutes, or until a toothpick inserted in the center emerges with moist crumbs.
09 - Allow to cool completely in the pan set on a wire rack. Lift brownies out using the parchment overhang, cut into squares, and serve.