Slow Cooker Chai Hot Chocolate

Ingredients
1 cinnamon stick or quill
2 whole star anise
4 whole cloves
1-2 drops Ginger essential oil
1 teaspoon ground cardamom
1/2 teaspoon freshly ground fennel seeds
1/2 teaspoon ground allspice
Freshly ground black pepper
8 cups (2L) milk
400g dark chocolate, finely chopped
Ground cinnamon, to serve

1. Cook the cinnamon stick or quill, star anise, cloves, cardamom, fennel and allspice in a small frying pan over high heat, stirring, for 30 secs on until aromatic. 
2. Transfer to a slow cooker. Season with pepper. Add the milk, chocolate and Ginger essential oil. Cook on low, stirring occasionally, for 1 hour or until mixture is smooth and heated through.
3. Divide among serving glasses. Sprinkle with chocolate and cinnamon.