Remove white papery skin from garlic heads (do not peel or separate the cloves). Wrap each head separately in foil. Bake at 350° for 1 hour; cool 10 minutes. Separate cloves, and squeeze to extract garlic pulp. Discard skins. Place garlic pulp and 1 cup corn in a blender or food processor; process until smooth. Set aside.
Cut a piece of foil long enough to fit around a 2-quart soufflé dish, allowing a 1-inch overlap; fold foil lengthwise into thirds. Lightly coat one side of foil and bottom of dish with cooking spray. Wrap foil around outside of dish, coated side against dish, allowing it to extend 4 inches above rim to form a collar; secure with string or masking tape.
Place flour in a medium saucepan. Gradually add milk, stirring with a whisk until well blended. Stir in garlic mixture; bring to a boil over medium heat. Cook 1 minute or until thick, stirring constantly.
Preheat oven to 400°.
Place eggs in a large bowl. Gradually add hot milk mixture to eggs, stirring constantly with a whisk. Stir in remaining 1 cup corn, chives, and next 5 ingredients (chives through red pepper). Place egg whites and cream of tartar in a large bowl; beat with a mixer at high speed until stiff peaks form. Gently stir one-fourth of egg white mixture into corn mixture. Gently fold in remaining egg white mixture. Pour mixture into prepared dish. Bake at 400° for 10 minutes. Reduce oven temperature to 350° (do not remove soufflé from oven); bake an additional 45 minutes or until puffed and golden. Carefully remove foil collar. Serve immediately.