Line 36 mini muffin pans with mini liners. Set aside.
In a saucepan, heat the cream and sweetened condensed milk until steaming. Remove from the heat and add the chocolate. Let the mixture sit for 10 minutes.
Return the pan to the stove over low heat and whisk vigorously until the chocolate is completely melted and the mixture is thick and shiny. Add a chocolate hazelnut flavoring and whisk to combine. Add 2 tablespoons of chocolate mixture to prepared mini-muffin pans. Top some with mini marshmallows, Sweets and Treats sprinkles and leave some plain, if desired. Store covered in the refrigerator for 2 weeks. Bring to room temperature before using.
To use: Warm 8 - 10 ounces of whole milk in a saucepan until steaming but not boiling. Transfer to mug and add one hazelnut hot chocolate drop to mug. Stir until dissolved.