Add the milk, white chocolate, crushed candy canes, and vanilla to a 5-quart or larger slow cooker.
Cover and cook on HIGH for 1 hour and 30 minutes. Stir every 15 minutes.
Pour hot chocolate into mugs and top with whipped cream and crushed candy canes for garnish. Serve warm.
Notes
I crushed up 8 candy canes. That gave me the 1/2 cup for the recipe with enough extra to garnish our drinks. You can use starlight peppermint candies if you can't find candy canes.