First, begin by preparing some of your ingredients. Peel and rinse the potatoes. Then cut them into cubes. Dice the onions, mushrooms, garlic, and parsley and set aside. Thoroughly rinse and drain the lentils from the can.
Set a big pot of water to boil. When boiling, add a pinch of salt, add the potatoes, reduce the heat to medium and boil about 20 minutes or until the potatoes are fork tender. Remove from the water AS SOON as they are cooked through.
Fill a medium saucepan 3/4 of the way with water and set aside.
In a skillet, add the diced onion, garlic and olive oil. Saute until translucent and soft.
Add the mushrooms to the skillet. Saute another couple of minutes until they're softened.
Add the diced tomatoes, tomato sauce, veggie broth, lentils, spices and herbs and saute another 3-5 minutes until the sauce has thickened and all ingredients are incorporated. Then set aside.
Preheat the oven to 400.
Set the water in the medium sauce pan to boil. Once boiling, blanch the corn for about 2-3 minutes. Drain and set aside.
In the big pot, mash the potatoes with a masher or big spoon. Add the milk, butter, onion and garlic powder, and salt and pepper. Fold in with a spatula.
In a 9x13 pan, first add the lentil mixture. Spread it out evenly.
Then evenly layer the corn on top.
Then layer the mashed potatoes on top of the corn.
Add to the oven and bake about 30 minutes until golden brown.
Remove from the oven and let sit so that the juices can settle. Slice into squares and serve.