Place the cashews in a bowl and pour boiling water over them. Set aside to soak. Peel and finely dice the onion and garlic. Clean the mushrooms and slice them thinly. Wash or peel the potatoes and cut them into small cubes, about 1 centimeter in size.

Heat olive oil in a large pot and sauté the onion and garlic over medium-high heat with a generous pinch of salt. Once the onions are translucent, add the mushrooms and potatoes, crumble the stock cube over the pot, and sauté the vegetables over medium heat for about 10 minutes, until the mushrooms are nice and soft and juicy. Stir regularly to prevent burning.

Meanwhile, drain the cashews and place them in a blender with the milk and water. Place the beans in a colander and rinse them under running water. Add about one-third of the beans to the blender and blend with the remaining ingredients until smooth.

Pour the cashew bean cream into the pot, add the remaining beans and thyme, cover, and simmer gently for 20 minutes, stirring regularly, until the potatoes are nice and soft.

Remove the thyme, add the Parmesan cheese and season the bean stew with salt and pepper.