Cook the lentils and water in a large pot over high heat until it starts to boil. Lower the heat, cover the pot, and let it bubble gently for 15 minutes. Gather your spices and other ingredients in the meantime.
Next, add the chopped mushrooms, garlic powder, oregano, tamari, tomato paste, olive oil, and nutritional yeast. Cook for another 15 minutes, stirring frequently, until all the water is absorbed. Then keep cooking and stir in the flour for a few more minutes until the mixture is fairly dry. Make sure it doesn’t burn.
Cool the lentil mixture to near room temperature, then form them into burger-sized patties (or meatball-sized balls) with your hands. Put on a parchment-lined baking sheet and bake at 300F for 30 minutes. They will be nice and crisp on the outside and a little bit golden-brown.
Since everyone in our house has different tastes, I usually serve dinner in all its separate parts, and people can assemble their own plates however they like: pasta, sauce, burger buns, condiments, and finally the lentil mushroom burgers/meatballs. Serve hot, with optional fresh basil on top if you like. Buon appetito!