1/3 cup sugar
1/4 cup unsweetened cocoa powder
1/4 teaspoon salt
3 cups milk, divided
3/4 teaspoon vanilla
1 cup heavy cream
1 square (1 ounce) bittersweet chocolate
1 square (1 ounce) white chocolate
3/4 cup whipped cream
6 teaspoons mini chocolate chips or shaved bittersweet chocolate
Combine sugar, cocoa, salt and 1/2 cup milk in medium bowl. Beat until smooth. Pour mixture into slow cooker. Add remaining 2 1/2 cups milk and vanilla. Cook on low 2 hours.
Add cream. Cover and cook on low for 10 minutes, stir in bittersweet and white chocolate until melted.
Pour hot chocolate into 6 coffee cups. Top each with 2 tablespoons whipped cream and 1 teaspoon chocolate chips.