Layer peppers and onion over bottom of a shallow 12 x 7" microwave-safe baking dish. Sprinkle with half of the basil and half the pepper. Cover dish with plastic wrap, leaving one corner open to vent. Microwave on High (100%) setting for 2-3 minutes, or until vegetables are partially tender.

Arrange fillets over vegetables, with thickest portions toward outside, and sprinkle with remaining basil and pepper. Dust lightly with paprika. Cover with vented plastic wrap and microwave 7-9 minutes longer, or until fish flakes easily with a fork, rotating dish 1/2 turn after 4 minutes. Let stand, covered, 3 minutes before serving with lemon wedges.