Place whole bell peppers directly on grid on natural gas barbecue.
Grill peppers over medium heat, turning occasionally until blackened on all sides, about 15 - 20 minutes. Place hot peppers in a bowl; cover with plastic wrap. Allow peppers to steam for 5 - 10 minutes. Peel peppers under cold running water. Remove stems and cut peppers in half. Remove seeds and ribs. Use as directed in recipe.