Heat the tawa/grill. Cut the peppers into quarters, deseed them and arrange them, cut side down, on the tawa/grill pan. Grill for 8 minutes, or until their skins blister and blacken. Transfer them to a bowl and cover.
When the peppers are cool enough to handle, peel them and dice finely. Place them in a bowl with the chilli, lemon zest and 2 tablespoons of oil. Stir in the parsley, reserving a little for a garnish, and set aside.
Bring a large pan of salted water to the boil and cook the spaghetti according to the instructions on the packet. Drain and keep the pasta warm.
Meanwhile, gently remove the tough white muscle and the coral, if attached, from the scallops and pull away any dark digestive thread. Then rinse and pat each scallop dry. If they are very large, cut them into bite-size pieces. Toss them in 1 tablespoon of oil and season with salt and pepper to taste.
Heat a large nonstick frying pan. When the spaghetti is nearly cooked, sear the scallops for 2-3 minutes on the grill pan, turning them over once. They should be very lightly browned but opaque and cooked through if cut open. Do not overcook them or they will be tough.
Heat 1 tablespoon of oil in a nonstick frying pan. Fry the garlic for 1 minute then stir in the roasted pepper mixture. When it is warm, add the scallops, lemon juice and spaghetti. Mix thoroughly and garnish with the reserved parsley and a sprinkling of black pepper. Serve the pasta with lemon wedges, and freshly grated Parmesan, if you like.