01 -
In a medium saucepan, add the rinsed lentils and cover with water. Bring to a boil, then reduce heat and simmer for about 20-25 minutes until tender but still plump. Drain any excess water and set aside.
02 -
In a large skillet, heat a splash of olive oil over medium heat. Add the chopped onion and sauté until translucent, about 3-4 minutes. Stir in the garlic and cook for an additional minute.
03 -
Add the diced carrots, celery, and chopped mushrooms to the skillet. Cook for about 6-7 minutes, stirring frequently until all the vegetables are slightly softened.
04 -
Add the cooked lentils to the skillet, followed by vegetable broth, tomato paste, thyme, rosemary, soy sauce, and season with salt and pepper. Stir well and let it simmer for 10 minutes, allowing the flavors to meld. Stir in the frozen peas at the end.
05 -
While the filling is simmering, boil the chopped potatoes in a large pot of salted water until tender, about 15-20 minutes. Drain and return to the pot. Add milk, butter or olive oil, then mash until smooth. Season with salt, pepper, and nutmeg if desired.
06 -
Preheat your oven to 400°F (200°C). In a large baking dish, spread the lentil filling evenly at the bottom. Top with the mashed potatoes, smoothing it out with a spatula. Use a fork to create texture on the surface for a crispier topping.
07 -
Place the dish in the preheated oven and bake for 20-25 minutes until the top is golden brown and slightly crispy.
08 -
Let it cool for a few minutes before serving.