Slice off the tops and bottoms of the mushrooms. Cut them into ½-inch-thick slices. (Optional step: Use an apple corer or similar kitchen tool to remove the center of each mushroom slice.) Add the finished slices to a large mixing bowl, and add 10 cups water and the tamari. Marinate for 3 to 5 hours, or overnight in the refrigerator.

Add the cornmeal, flour, chili powder, paprika, onion powder, garlic powder, basil, salt, and pepper to large mixing bowl. Drain the mushrooms, and dredge in the breading mixture, using your hands to fully coat each mushroom slice.

Add the cooking oil to a deep skillet, and heat on medium-high heat until the oil begins to bubble. Add the mushroom slices and fry for about 7 minutes, or until they are golden brown. Remove from the oil and serve with our Marinara Sauce.