1 Preheat oven to 350°F.  Grease a 9x13 inch baking dish. 2 Cook noodles according to package directions.  Drain and place in a large bowl. 3 Add spinach, soy milk, onion soup mix, eggs and margarine.  Mix to combine. 4 Transfer to prepared baking dish and bake uncovered for 45 minutes or until lightly browned on top. *Here is the link for the homemade onion soup mix.