Heat a large pot with a tablespoon of canola oil over medium-high heat. Add the onion, garlic, celery, and bell pepper and cook until the onion is translucent, about 5 minutes.
Add the vegetable broth and potatoes. Bring to a boil and reduce the heat to a simmer. Cook for 10 minutes. Add the corn, coriander, chili powder, oregano, and cumin. Cook until the corn and potatoes have softened.
Turn off the heat and use an immersion blender or a stand blender to mix until smooth. Turn the heat back on to medium and add the coconut milk. Cook until heated. Flavor with salt and pepper to your liking. Serve with sliced scallions and cilantro.
