How to Make It
Place tequila, lime juice, and 1/4 cup jam in a cocktail shaker; muddle mixture. Fill shaker with ice. Cover and shake until thoroughly chilled. Place 1 tablespoon jam into bottom of each of 2 highball glasses. Fill glasses with ice, and strain tequila mixture into glasses. Top off cocktails with sparkling water. Garnish with grilled peach slices and lime twists.