Finely chop onions and mushrooms, fry in oil for 3-5 minutes. Add walnuts, sunflower seeds, soy milk, whole grain crumbs and basil and stir well. Bake in an oiled baking pan at 180 ° C for 45 minutes.
For Gravey sauce, mix the oatmeal and warm water with a hand blender. Put the mixture in a saucepan and simmer over low heat. Stir constantly until the liquid thickens. Add the yeast extract and serve for frying.