Special equipment: 2 margarita glasses
Rub the lime wedge around the rims of both margarita glasses and then dip the rims into a plate of sea salt, turning slowly to heavily coat. Fill each glass with 1/2 cup of crushed ice. Working directly over a glass, press the flesh side of one lime half against the serrated edge of a small knife. While squeezing, turn the lime clockwise until all the juice and pulp have been scraped into the glass. Repeat for the remaining lime half and margarita glass. Add half of the tequila to each glass. Then top each with 1/4 cup of the grapefruit soda. Stir with a spoon and serve immediately.
A viewer or guest of the show, who may not be a professional cook, provided this recipe. It has not been tested for home use.