Into a cocktail shaker add ice, cranberry juice, peppermint syrup, Blanco or silver tequila, and freshly squeezed lime juice.

Secure the lid and shake vigorously for thirty seconds.

Strain the cocktail between two rocks glasses and top each with chilled grapefruit soda.

Garnish each with a half slice of fresh grapefruit, and drop three whole cranberries into each glass.

Serve.