Position a rack in the middle of the oven and preheat to 400 degrees . Position a rack on a baking sheet. In a shallow dish, toss the panko with the melted butter. Season with the thyme, chives, Old Bay, onion powder, garlic powder and citrus zest.
Season the fish with salt. place the egg whites in another shallow dish and beat until frothy. Coat the fish in the egg whites, then gently press into the panko mixture to coat evenly. Place on the rack-lined baking sheet. Bake the fish until the breading is a deep golden-brown, about 20 minutes.
Meanwhile, using a food processor, chop the parsley and mint. Scrape the herbs into a dish and return the processor bowl (do not rinse). Pulse the peas until coarsely chopped.
In a large skillet, heat the EVOO with the remaining 2 tbsp. butter over medium heat. Add the shallots and cook for 5 minutes. Add the stock and the peas and cook over medium-high heat for about 10 minutes for fresh peas, 4 minutes for frozen. Season with salt, pepper and the herbs.
Spoon the peas onto plates and top with the fish. Douse with vinegar.