Cook lasagna in plenty of boiling water for 8 to 10 minutes. Drain and rinse in cold water. Prepare the spinach by washing it in several changes of cold water. Place in a heavy bottomed pot and cook gently without adding more water, for 6 to 8 minutes. When cooked, strain off excess water and chop finely. Return to the pot and season well. Put pan on a gentle heat, add margarine & marjoram, stir and then remove from heat. When the spinach has cooled, mix in the ricotta. Check the seasoning. To prepare sauce, saute the sliced mushrooms in margarine, reduce heat and continue to cook for 10 minutes in a covered pot so that plenty of juice is extracted. Add the stock and simmer another 5 minutes. Puree in a blender for a few seconds. Add soy sauce and season to taste. Lightly oil a square 3 pint dish, spoon in some of the spinach, cover with 2 or 3 pieces of lasagna and then a coat of the mushroom sauce. Repeat, ending with the mushroom sauce. Sprinkle with grated cheese. Bake at 200ºC . for 35 to 40 minutes. Serve immediately. From WWiVNet. Electronic format by Cathy Harned.