Recently, I had this dish at a cookout and liked it a lot.  It is a nice summer dish.
The source is Barefoot Contessa. 

Kosher salt
Good olive oil
3/4 lbs. orzo pasta
1/2 cup freshly squeezed lemon juice
Freshly ground black pepper
2 lbs (16-18 count) shrimp, peeled and deveined
1 cup minced scallions, white and green parts
1 cup chopped fresh dill
1 cup chopped fresh flat-leaf parsley
1 small cucumber, unpeeled, seeded and medium diced
1/2 cup small diced red onion
3/4 lbs. good feta cheese, large diced

Preheat the oven to 400 degrees F. 

Fill a large pot with water, add 1 tablespoon of salt and a splash of oil, and bring the water to a boil.  Add the orzo and simmer 9 to 11 minutes, stirring occasionally, until it's cooked al dente.  Drain and pour into a large bowl.  Whisk together the lemon juice, 1/2 cup olive oil, 2 teaspoons salt and 1 teaspoon of pepper.  Pour over the hot pasta and stir well.

Meanwhile, place the shrimp on a sheet pan, drizzle with olive oil, and sprinkle with salt and pepper.  Toss to combine and spread out in a single layer.  Roast for 5 to 6 minutes, until the shrimp are cooked through.  Don't overcook!

Add the shrimp to the orzo and then add the scallions, dill, parsley, cucumber, onion, 2 teaspoons salt and 1 teaspoon pepper.  Toss well.  Add the feta and stir carefully.  Set aside at room temperature for 1 hour to allow the flavors to blend or refrigerate overnight.  If refrigerated, taste again for seasonings and bring back to room temperature.

Serves 6 as an entree or 12 as a side dish.

mothermitzi