1 1/2 lbs. peeled and de-veined large frozen shrimp thawed, tails removed
2 tablespoons chopped fresh mint plus more for garnish
4 ounces feta cheese
Preheat oven to 475 degrees with rack set in upper third. Heat oil in a large skillet over medium. Add scallions, garlic, and oregano; cook, stirring, until fragrant, about 1 minute. Add tomatoes. Cook over medium, stirring occasionally, until no liquid remains in skillet, 10 to 15 minutes. Season with salt and pepper.
Add shrimp and mint to skillet. Stir to combine; transfer to an 8-inch square (or other shallow 2-quart) baking dish. Crumble feta over top.
Bake until liquid is bubbling, cheese is beginning to brown, and shrimp in center of dish are opaque, 15 to 20 minutes.