Put a high-sided sauté pan or dutch oven on medium heat. Add the oil and let it come to temperature. Add in the onion and cook, stirring occasionally, until it is softened and starting to become transluscent, around 4-5 minutes.
Add in the garlic and spices. Season with salt and stir to combine. Cook another 2-3 minutes or until the garlic has softened and the spices are aromatic.
Add in the potato and half of the corn kernels. Stir and cook in the oil for about 4-5 minutes.
Pour in the oat milk and bring to a simmer. Stir in the nutritional yeast. Simmer for 10-15 minutes or until the potato is tender.
Reduce the heat to low and use an immersion blender to blend the soup until it is mostly smooth. There's a lot going on in there so don't worry if there is still some texture in the mix! Season with salt and pepper as needed.
Raise the heat back to medium, add in the remaining corn, and simmer another 7-10 minutes, or until the corn is cooked.
Portion into bowls and top with the mussels, chili oil and more fresh ground black pepper. Serve warm!