In a cocktail shaker, add tequila, grapefruit juice, 1 teaspoon of Jalapeño Chile Powder, and simple syrup. Shake until well combined!
Coat the rims of your glasses with the lime juice (rub the lime around the rim). Spread the remaining Jalapeño Chile Powder on a small plate, and dip the rims of the glasses into the powder, fully coating the entire way around. If the chile powder is too spicy for you, you can mix in some sugar to cut the spiciness down!
Add ice to glasses and pour cocktail mixture over ice.
Top with club soda for some bubbles and enjoy!