In a medium, microwave safe bowl, add in chopped chocolate and coconut oil. Microwave in 20 second increments, stirring occasionally to make sure chocolate doesn't burn.
Pour about a tablespoon's worth of melted chocolate into 12 cavities of the candy mold or into lined cupcake pan. Place candy molds into the freezer for about 5 minutes.
Next, add about a teaspoon's worth of dulce de leche on top of cooled chocolate. Top off with mini marshmallows. Lastly, add another tablespoon's worth of melted chocolate over the marshmallow layer. Place in the freezer for about 20 minutes and enjoy. Don't forget to add a bit of flaky salt!