Peel and dice the onion so it cooks evenly and quickly. Dice the celery into small pieces. If using fresh corn, cut the kernels off the cob before cooking.
Heat olive oil in a large pot over medium heat. Add the onion and celery, stirring often, until the onion turns golden and soft, about 7–10 minutes.
Stir in the fresh corn kernels and cook for about 5 minutes, letting them release their natural sweetness.
Add the miso paste and ground black pepper, stirring until the vegetables are coated.
Pour in the vegetable broth, reduce heat to medium-low, and let the soup gently simmer for 20 minutes to deepen the flavors.
Remove from heat, then stir in the toasted sesame oil and lime juice. Blend with an immersion blender until smooth. For a chunkier texture, set aside one cup of soup before blending and stir it back in.
Season with salt to taste, then ladle into bowls. Garnish with fresh herbs, an extra drizzle of sesame oil, or a sprinkle of fresh corn kernels. Enjoy!