Wash and coarsely grate the zucchini, drain in a colander and then transfer to a bowl. Peel and mash the garlic. Add the thyme, egg, cornstarch and nutmeg to the zucchini and season with salt and pepper. Bake small portions of the mixture in hot oil on both sides as golden brown cookies. Mix the creme fraiche with salt, pepper and lemon juice. Arrange the zucchini rösti with creamy cream and beef cured ham on plates.