Line a large rimmed baking sheet with parchment paper or a silicone baking mat.

Melt the dark chocolate chips using a double boiler or in a microwave-safe bowl in 30-second intervals, stirring until completely smooth.

Pour the melted chocolate onto the prepared baking sheet and spread into an even layer approximately 1/4-inch thick using an offset spatula.

Arrange the pretzels over the melted chocolate, pressing down lightly to ensure they adhere.

Melt the white chocolate chips and use a spoon or piping bag to drizzle it decoratively over the pretzels and dark chocolate.

Sprinkle the coarse sea salt evenly across the surface while the chocolate is still wet.

Place the baking sheet in the refrigerator for at least 60 minutes until the chocolate is fully set and firm.

Remove from the refrigerator and break the bark into irregular pieces by hand or using a sharp knife.