Add the sugar and cocoa powder to a slow cooker and whisk to combine.
2. Step
Add the milk and whisk to incorporate. Turn the heat setting to high, cover, and warm for 30-60 minutes, until steaming. Once steaming, reduce the heat setting to warm.
3. Step
Add the peppermint schnapps. Whisk to combine and to ensure the sugar and cocoa powder are fully dissolved. Add the marshmallows.
4. Step
Ladle into mugs and top with whipped cream and crushed peppermint candies.
