In a medium or large saucepan, add the lite coconut milk and water. Bring to a gentle boil, then gently whisky in the cornmeal gradually and stir together.

Bring the mixture to a boil and stir frequently. Allow to boil, and as soon as the polenta begins to spatter, lower the heat. Continue to cook, stirring frequently with a wooden spoon or silicone spatula, until the polenta begins to pull away from the side of the saucepan and is very thick, about 45 minutes.

Add the nutritional yeast and vegan butter (if using), and stir. Season with salt and pepper to taste. If the polenta starts to clump, whisk vigorously until the clumps are gone.

Once the polenta is on the stove, prepare the ragú. Heat the 2 tablespoons olive oil in a large 12-inch nonstick skillet over medium heat. Add the onion and cook for 5-6 minutes, or until lightly browned.

Add the mushrooms and fresh thyme leaves, and cook, stirring occasionally, until the mushrooms are golden, about 5-6 minutes.

Add the cherry tomatoes, black pepper, and 1 1/4 teaspoons kosher salt. Cook until the tomatoes burst, about 6-7 minutes. If the tomatoes or mushrooms start to burn, lower the heat. Pour in the marinara sauce and stir to coat the vegetables.