How to Make It
Without shaking or tilting the can, carefully open 1 (13.66-oz.) can chilled coconut milk. Remove solidified cream from top, reserving liquid, and place in a bowl. Add 2 tablespoons powdered sugar and 1 teaspoon vanilla extract, and beat with an electric mixer until medium peaks form, about 3 minutes. Chill until ready to use.
Whisk together remaining coconut milk liquid, 1 quart unsweetened coconut milk (such as So Delicious), 3/4 cup granulated sugar, and 1/4 cup unsweetened cocoa in a medium saucepan. Bring to a simmer over medium, stirring constantly. Cook, stirring constantly, until sugar is dissolved and mixture is hot, about 10 minutes.
Remove from heat, and whisk in 6 ounces 60% cacao bittersweet chocolate, 3/4 teaspoon cinnamon,1/4 teaspoon kosher salt, and 2 teaspoons vanilla extract.
Pour into 4 serving cups, and top with whipped coconut cream, a sprinkle of ground cinnamon, toasted coconut, and shaved chocolate