In a cocktail shaker, combine the horchata cream, tequila, rum, syrup and bitters.
Add crushed ice, cover and shake until well chilled, about 15 seconds.
Strain into a chilled Collins glass and fill with more crushed ice.
Float the sherry on top of the cocktail, then top with a scoop of crushed ice so it’s mounded slightly over the the rim.
Stand a mint spring in the ice, then stab a cherry with a cocktail toothpick and lay it over the rim.
Grate a light dusting of fresh nutmeg over the cocktail to serve.