Melt 1 ¾ cup of chocolate in the microwave. Pour the melted chocolate onto parchment paper and use a rubber spatula to spread it into the shape of a rectangle.
Layer pretzels on top of the chocolate till it is covered.
Dice the green apple and dab it with a paper towel to get rid of as much moisture as you can to prevent the caramel from becoming runny.
Microwave caramel in 15 second intervals. Stir until all melted. Mix the apples into the caramel then spread it on top of the pretzels. Move it to the fridge and let it sit for 30 minutes.
Remove from fridge and melt the remaining chocolate and drizzle it on top. Return to the fridge for an hour then take it out and cut the bark in to bite size pieces.