Heat grill to medium-high heat.
Place fish fillet onto center of large sheet heavy-duty foil. Bring up foil sides. Pour beer over fish. Fold to make packet.
Place packet on grill; cover with lid. Grill 7 min. Carefully open foil packet. Sprinkle cheese over fish; reseal packet. Cover grill with lid; grill 5 min. or until fish flakes easily with fork.
Remove fish from packet to serving platter; sprinkle with nuts and parsley.