Preheat oven 250F.
Place a large pot of water to a boil over high heat. Salt water and cook pasta to al dente. Heads up: you need to reserve a ladle of starchy cooking water for pasta and peas just before draining.
While water comes to a boil, set up three dishes for breading the filets: In the first, combine the flour with the Old Bay. In the second, beat the eggs with a splash of water. In the third, combine the breadcrumbs, 1/2 cup Parmigiano, thyme and lemon zest. Dip each fish filet first in the flour mixture, then the egg and finally in the breadcrumbs. Place the coated filets on to a sheet try and reserve.
While the pasta is cooking, preheat a large skillet over medium to medium-high heat with 1/4 cup of EVOO, 4 turns of the pan. Saute 2 filets at a time 6-7 minutes until golden, turning once. Place the first batch in low oven on cooling rack over baking sheet to keep crisp. You'll need to add 2 tablespoons more EVOO to pan for next batch and let oil get hot again before cooking second batch.
While fish cooks, heat 1 tablespoon EVOO, 1 turn of the pan to a skillet over medium heat. Add onions and garlic and cook to tender, 5-6 minutes. Add the peas and butter to the skillet with the onions and garlic and heat the peas through. Add starchy cooking water, drained pasta. Turn off the heat, toss with mint, parsley and a couple of handfuls of cheese, season with salt and pepper.
Serve fish alongside pasta. Cut lemon into wedges and serve for topping fish.