Vegetarian Shepherd's Pie with Sweet Potato Topping

First, peel the potatoes and sweet potatoes, cut them into coarse pieces, and bring them to a boil in a large pot with enough water. Cook over medium heat for about 15–20 minutes until soft. Meanwhile, peel the onion and garlic, finely dice the onion, and press the garlic.

Clean the mushrooms and cut them into small pieces (about the size of the beans). Place kidney beans and lentils in a sieve, rinse, and drain well.

Once the potatoes are soft, drain the water. Add the milk and a pinch of salt, and mash or whip everything into a smooth consistency. Set aside warm.