In a 3-qt. slow cooker, combine the first 6 ingredients. Cook, covered, on low 6-8 hours or until vegetables are softened., Puree soup using an immersion blender, or cool soup slightly and puree in batches in a blender. Return to slow cooker and heat through., In a small skillet, heat oil over medium heat. Add corn; cook and stir until golden brown, 4-6 minutes. Sprinkle soup with pepper. Garnish with corn and cilantro.