Preheat oven 350. In saucepan, bring potato, carrot, onion, 1c water and salt to boil over medium high heat. Lower to a simmer and cook until potato and carrot are tender <about 10 mins>. Meanwhile, thaw frozen broccoli in colander under hot running water, then set aside and drain well.

When potato mixture has finished simmering, pour into a blender and add tofu, yeast, lemon juice and garlic. Blend until very smooth and creamy. Pour into a shallow, greased 1 1/2-2qt casserole. Add broccoli, rice, mushrooms and 3/4c water. Stir well and smooth top of casserole.

Bake 40 mins, until golden and bubbling. Per serving-279 cals, 16G protein, 3G fat, 46G carbohydrates, 0 cholesterol, 753MG sodium, 7G fiber.