Boil the water, add the amaranth and once again boil, reduce heat, and simmer for sandwiching about 20 minutes. Meanwhile, cook and clean handle spinach, tomatoes and peel and cut in large pieces. To peel tomatoes easily put the water to boil, put in boiling water the tomatoes one at a time for 20 seconds, then remove them and put in a bowl with ice water, then peel. Heat and olive oil, which must be added the onion and garlic (finely chopped) - cook them and them for about 2 minutes. Then add tomatoes, mushrooms, basil, oregano, salt, pepper and 1 tbsp water. Now you need to put here and choke already spinach, cook another 10-15 minutes without remembering to stir occasionally. Lightly mash the tomatoes and finally mix and amaranth. There is another way to serve - to pour the sauce itself amaranth.