Drain the tomato juices into a one-cup measuring cup. In a medium bowl, toss the shrimp with the drained tomatoes. Add chicken broth to the tomato juices in the measuring cup to measure one cup. Heat in the microwave until very warm. In a separate bowl, combine the couscous with the hot tomato broth and let the couscous absorb the liquid.
Layer two sheets of foil on top of each other to create strong baking vessels. You'll be assembling four packets. Spray the center of each with nonstick spray.
Divide the couscous between the foil packets, spooning it into the center of each.
Spoon shrimp and tomato mixture on top of the couscous, dividing to make sure that each foil packet gets 8 shrimp. Add zucchini and onion on top of each packet, add a sprinkle of kosher salt, and then divide the lemon slices among the packets.
Wrap the foil and crimp the edges to seal. Grill sealed-side-up until the shrimp are cooked through, 12 to 14 minutes.
Remove the packets from the grill and carefully open them. Sprinkle with feta cheese and parsley and serve.
Notes
Alternately, you can cook these foil packets in the oven on a rimmed baking sheet at 350℉.
If you are counting WW Points, be sure to use reduced fat feta cheese crumbles.