In a small saucepan, bring sugar, water, and orange zest to a boil over high heat. Reduce to a simmer and cook until sugar dissolves, for approx. 3 minutes.
Let syrup cool in a bowl. In a blender, puree Creative Gourmet Frozen Watermelon Chunks until smooth.
Strain through a fine-mesh sieve, pressing on solids, into a jug (you should have about 1 cup juice). Stir in syrup, lime juice, and tequila.
Fill salt-rimmed glasses with ice, then pour margarita mixture over top.
