Put 2-3 tablespoons of water on one plate and some sugar on a second plate. Dip the edges of the glasses first just into the water, then into sugar. Let dry briefly before turning them over.
Peel the grapefruit so that the white skin is completely removed. Dice grapefruits, remove seeds if necessary. Place in a blender with sugar, tequila, grenadine, honey and crushed ice.
Mix finely until a creamy consistency is obtained. Pour into the prepared glasses.
Tip: For the Mango Frozen Margarita (left in the picture) for 4 glasses cut 2 ripe mangoes from the stone. Peel and chop the flesh. Put the juice of three limes, 4 tsp. sugar, 4 tsp. orange liqueur, 100 ml white rum, mango cubes and 12 ice cubes into a blender and chop finely until a creamy, sorbet-like consistency is obtained. Pour into glasses.