Season the scallops with pepper only and set aside.
In a 10 to 12-inch non-stick pan, heat 2 tablespoons of the olive oil until smoking. Place the scallops in and do not move them. Allow them to cook until crisp and golden brown, unmoved for 5 to 6 minutes.
In a 12 to 14-inch saute pan, heat remaining oil until smoking over high heat. Add the shallots and saute until softened, about 3 to 4 minutes. Add the mushrooms and toss 3 to 4 minutes until softened. Add vinegar and then the frisee. Toss quickly, season with salt and pepper and divide among 4 plates. Without turning the scallops, remove and arrange 3 on each salad. Drizzle with the high-quality oil and serve.