1.   Core and chop the apples (but leave the peel on). Place the pieces in a large bowl and sprinkle with lemon juice to prevent browning,
2.   Line a rimmed baking sheet at least 10 by 12 inches with parchment paper. Melt the chocolate chips in a small saucepan over low heat on the stovetop, or in a microwave-safe bowl at 30-second intervals in the microwave. Spread all but about 1 tablespoon of the melted chocolate over the parchment into a 10 by 12-inch rectangle.
3.   Scatter pretzels in an even layer on the surface of the chocolate.

4. Place the caramel sauce in a microwave-safe bowl and microwave for about 20 seconds, then spread all but about 1 tablespoon over the pretzels.

5. Top with the apple pieces. Drizzle the reserved chocolate and caramel over the bark. Freeze until hardened, at least 2 hours. To serve, break with a clean hammer (fun way) or chef’s knife (more normal way. Store leftovers in an airtight container in the freezer.