Preheat oven to 350F and coat a 9-inch square baking pan with cooking spray. In a medium sized mixing bowl, add creamed corn, whole kernel corn, vegan sour cream, and vegan butter. Stir well to combine.

In a separate bowl, whisk together cornmeal, flour, sugar, baking powder, and salt. Pour into wet ingredients and stir until incorporated.

Transfer the corn casserole mixture to the prepared baking dish and spread into an even layer.

Bake for 1 hour, until slightly golden on the edges. Remove from oven and let cool for at least 10 minutes. Slice and serve warm.