If using mahi-mahi, pat dry and halve. Season all over with half the garlic salt. Roast green beans and shallot, 15 minutes. Add mahi-mahi to baking sheet and follow same instructions as chicken for topping. Roast in hot oven, 4-5 minutes for medium. Consuming raw or undercooked mahi-mahi may increase your risk for food-borne illness.