Low-Cal Serrano Chile & Watermelon Margaritas

3 cups fresh watermelon puree (about 8 cups cubed seedless watermelon)

2 serrano chilies, sliced

1 1/2 cups fresh lime juice

2 cups silver tequila

1 cup simple syrup (1 cup sugar dissolved in 

1  cup hot water, then cooled)

1 tablespoon Cointreau

Combine all ingredients in a large pitcher and stir well. Add ice just before serving.

6 servings. Per serving: 240 calories; 0g fat; 25g carbs, 0mg sodium; 1g fiber; 1g protein