Broiled Herb-Marinated Spring Onions

Broiled spring onion bulbs are sweet and juicy; their greens, charred and chewy. Broil chicken or fish, set aside to rest under a foil tent, and then brown the onions to serve as a side. Soaking in warm water softens them and helps the marinade penetrate. Slip halved tomatoes under the broiler for the last 5 minutes to round out the meal.