1. Combine nectarines and orange juice concentrate in blender container. Cover and blend on high speed until smooth. Gradually add crushed ice, blending until mixture is slushy and measures about 5 cups. 2. To serve, place 1 tablespoon of the grenadine syrup in 8 stemmed glasses. Add orange-nectarine mixture. Top each glass with mint sprig and an orange slice on the rim for garnish. Note: 2/3 cup tequila can be added with the fruit in Step 1. Nutrition information per serving (including tequila): Calories........160 Fat.............0 g Cholesterol..0 mg Sodium......1 mg Carbohydrates...29 g Protein........1 g