Step 1

Combine all ingredients except marshmallows in a slow cooker and stir to combine.

Step 2

Cook, covered, until everything is melted, stirring occasionally, 2 hours on LOW.

Step 3

Ten minutes before serving, add marshmallows and let them get melty.

Step 4

Garnish with more mini marshmallows, and additional toppings crushed peppermint, chocolate shavings, chocolate syrup, whipped cream, caramel sauce, etc