2 oz tequila
2 oz freshly squeezed grapefruit juice
1/2 oz freshly squeezed lime juice
Splash lemon-lime soda (Diet Sprite or Diet 7UP is ideal)
Combine all ingredients in a cocktail shaker with ice and shake well.
The higher the quality of the tequila, the better your drink. At the very least, select a brand that's labeled "100% agave." For a truly top-shelf cocktail, look for an anejo or reposado tequila, both of which are aged before bottling.
Limes should be room temp or warmer-not chilled. It makes it easier to squeeze the juice from the fruit. To get even more juice in your glass, microwave the lime on high for 20 seconds, cool, and then roll on a solid surface using the palm of your hand until you feel the flesh softening. Serve your fresca in a tall, narrow glass. The extra height helps keep the soda fresh and bubbling longer than shorter, wider glasses, which allow carbonation to escape quickly.
According to a new Israeli study published by the Journal of Agricultural and Food Chemistry, the antioxidants in grapefruit juice-particularly red grapefruit juice-can significantly lower cholesterol levels, helping in the fight against heart disease.