Stir in crawfish tails, lemon juice, half of the parsley, half of the green onions, and half a cup of shredded parmesan cheese until blended and melted. Cover the dish with the rest of the cheese and put it under a broiler for 4-6 minutes, until the cheese on top is melted, browning, and bubbly.
Garnish with remaining green onions and parsley.