Preheat the oven to 350° Fahrenheit and line 2 cookie sheets with parchment paper. Set aside. Place chocolate in a bowl set over a pan half filled with simmering water. Melt the chocolate, stirring occasionally. Once chocolate has melted, turn of the heat and leave the bowl over the pan until ready to use. This allows the steam to keep the chocolate viscous.
Cut each marshmallow in half and set aside. Arrange half the pretzels on one prepared cookie sheet giving them at least 2 inches of space (marshmallows spread, boo). Place a marshmallow half over each pretzel.
Place sheet pan in the oven for 5-6 minutes until marshmallows have melted and browned ever so slightly. Remove pan from oven and allow the marshmallows to cool and contract for at least 3 minutes. With a tiny cookie scoop or a measuring spoon, spoon about 1/4 teaspoon of dulce de leche over the melted marshmallows.
S'more that situation: Sandwich with another pretzel piece and flatten slightly. Remove chocolate from pot of simmering water and working quickly, dip half of each pretzel s'more in the melted chocolate and place on prepared sheet pan. Place the cookie sheet in the freezer for about 5 minutes or so to allow the chocolate to set.