Peel the potatoes and put them in a large pot filled with water. Boil them until they're tender. Mash them and let them cool for a while.
Chop the mushrooms, carrot and red bell pepper. Add them into your food processor and pulse until all ingredients are well mixed together.
Heat 2 tbsp of sunflower oil in a large skillet. Add the mixture above, diced onions, chopped dill and parsley, soy granules, eggs ( or egg substitutes + dry yeast flakes) and spices. Sauté for 10 minutes.
* I added the soy granules without boiling them because the mushrooms contain a lot of water and these soy granules will absorb all excess water.
Put some parchment paper on the bottom of a casserole. Divide the mashed potatoes in two. Place the first half in the casserole and spread it with a spatula. Add the filling. Place over the other half of mashed potatoes.
Heat your oven at 392Ëš. Put the casserole in the oven. Cook for 40 minutes.
Don't serve immediately. Let it cool for at least half an hour.
*Textured soy protein substitute: Use 1,5-2kg of mushrooms instead of just 1kg. Add 3-4 tbsp of breadcrumbs(optional). I used soy granules only for economical purposes.