In a slow cooker or large saucepan, add the heavy cream, milk, white chocolate chips, sweetened condensed milk, and vanilla extract. Stir gently until well mixed.

Set the slow cooker to low heat and cook for 2 to 3 hours, stirring every 20 to 30 minutes.

Once melted and creamy, add green and yellow food coloring a few drops at a time, stirring well after each addition until the desired color is achieved.

Serve warm, topped with optional mini marshmallows, whipped cream, or festive sprinkles.

For stovetop method, combine all ingredients in a medium saucepan, heat over medium until simmering (5-10 minutes), and stir frequently. Do not boil.