Step 1

Preheat the broiler with the oven rack in the upper third. Heat olive oil, orzo, and onion in large deep skillet. Cook over medium-high heat, stirring until orzo is golden, about 5 minutes. Add tomatoes and their liquid, breaking them up with a spoon. Add the water, oregano, and olives, and season with salt and pepper. Reduce heat to medium and cook, stirring until thick, 8–10 minutes.

Step 2

Season fish with salt and pepper and add to the skillet. Top with feta, drizzle lightly with oil, and broil until fish just flakes, 3–4 minutes. Sprinkle with scallions. Serve.