Preheat your oven to 350°F (175°C). Grease and line a baking dish with parchment paper.

. In a microwave-safe bowl, melt the dark chocolate chips and butter together, stirring until smooth.

. In a separate bowl, whisk together sugar, eggs, and vanilla extract until well combined.

. Gradually pour the melted chocolate mixture into the egg mixture, stirring until smooth.

. Sift in flour, cocoa powder, and salt, then fold gently until just combined.

. Pour the batter into the prepared baking dish and spread it evenly.

. Dollop spoonfuls of peanut butter onto the batter, then use a knife to swirl it into the chocolate mixture.

. Sprinkle chopped hazelnuts over the top.

. Bake for 25-30 minutes or until a toothpick inserted into the center comes out with moist crumbs.

. Allow the bars to cool completely in the dish, then drizzle with caramel sauce before slicing into squares.

Enjoy the rich chocolatey goodness with a perfect blend of nutty peanut butter and crunchy hazelnuts!