Heat the olive oil in a large pot over medium heat. Add the shallots and garlic and cook for about 8 minutes, until onions are soft and translucent, being careful not to brown them as it will darken the color of the fondue. Add the vegetable stock, potatoes, beans, and cashews. Partially cover and simmer until the potatoes are soft, approximately 20 minutes. Allow to cool slightly.

Carefully transfer mixture to a blender and add vinegar, cornstarch, miso, mustard, and salt. (Safety tip: if blending while hot, remove the knob from the blender lid and partially cover with a towel instead while blending to let steam escape.) Blend for about 1 minute or until completely smooth and glossy. Transfer the fondue mixture back to the pot. Cook fondue mixture over medium heat, stirring frequently to prevent scorching until the fondue is gently bubbling and slightly thickened, about 5 minutes. Stir in the nutmeg. Taste, adding additional salt if necessary.

Turn the broiler on high. Place the bread bowl on a baking tray. Pour thickened fondue mixture into the bread bowl and sprinkle with shredded mozzarella. Place the tray in the oven under the broiler for about 1 minute or until the cheese is lightly browned and bubbling. Transfer bread bowl to a platter or board and serve immediately surrounded by cubed bread cubes and “dippers” of your choice.