Heat grill pan over medium-high. Coat pan with cooking spray. Add zucchini ; cook 4 to 5 minutes on each side.
Place bread in a mini food processor; process until coarse crumbs form. Melt butter in a small skillet over medium-high heat. Add oil, red pepper, and garlic; cook 1 minute, stirring constantly. Add breadcrumbs to skillet; cook 5 minutes or until crisp, stirring occasionally. Stir in cheese, oregano, rind, and black pepper, sprinkle over grilled zucchini halves.
