Prepare 13x9-in. baking sheet with parchment paper and set aside.

In medium microwave-safe bowl, melt dark chocolate with 1 tsp. of oil in 20-second increments, stirring in between, until melted and smooth.

In separate bowl, melt white chocolate with remaining 1 tsp. of oil in same way.

Pour melted dark chocolate onto prepared baking sheet and spread into thin, even rectangle.

Spoon white chocolate over dark chocolate in several pools and use knife or skewer to swirl chocolates together to make marbled pattern.

Sprinkle crushed espresso beans and salt evenly on top.

Refrigerate 30 minutes, or until fully set.

Break bark into irregular pieces and store in airtight container in fridge.