Combine first three ingredients in a small bowl; set aside.
Prepare grill. Place bell peppers and onion on grill rack coated with cooking spray; grill 10 to 12 minutes or until tender. Set aside.
Place 1 crust on grill rack coated with cooking spray; grill 3 minutes or until puffy and golden. Turn crust, grill-mark side up; brush with half of oil mixture. Top with half of grilled vegetables and goat cheese. Cover and grill 4 to 5 minutes or until cheese melts and crust is lightly browned. Repeat with remaining crust and toppings.