In a medium pot, warm the half-and-half over medium heat until it is steaming, but do not let it boil. Whisk in the instant coffee, coffee liqueur, and cocoa mix. Keep it warm while you whip the cream.
In a cold bowl, whisk together the heavy cream, sugar, and vanilla extract until it forms soft peaks, or use a whipped topping if you prefer.
Pour the cocoaccino into mugs, dollop with whipped cream and garnish with chocolate shavings.