Spread dulce de leche on one side of half of the pretzels, and spread peanut butter on one side of the other half of the pretzels. Sandwich them together.

Melt the butter in a large, microwave-safe bowl on high power for about 1 minute. Remove the butter from the microwave and add the chocolate and corn syrup. Let the mixture stand for a minute, allowing the heat from the melted butter to begin to melt the chocolate. Then stir the mixture until completely melted and combined. If the mixture doesn't completely melt, continue to microwave on 50% power for 20 second intervals.

Dip one pretzel sandwich at a time into the chocolate mixture and remove it by scooping it out on the tines of a fork. With the pretzel sandwich still on it, gently slide the fork on the bowl rim to allow any excess chocolate to drip back into the bowl. Place the coated pretzel sandwiches on a baking sheet lined with parchment paper or in containers where they will not touch each other.

After all of the pretzel bites have been coated, lightly sprinkle a very small amount of sea salt over the tops. You may find that adding sea salt is unnecessary, depending on how salty your pretzels were. Place the pretzel bites in the freezer for at least an hour and store in the freezer until ready to eat.