Peel the potatoes and wash the zucchini. Slice both thinly with a vegetable slicer and layer in alternating rows in a baking dish. Heat the vegetable broth (it can also be dissolved instant broth) together with the cream and milk in a saucepan. Press in the garlic, add rosemary and butter. Bring the mixture to the boil briefly and season with salt, pepper and a pinch of nutmeg. Then pour the mixture over the layered potatoes and zucchini, sprinkle with the cheese and bake for 20 minutes at 200 ° C.