Preheat the oven to 180 ° C (top / bottom heat). Peel the potatoes. Cut the apples, pumpkin and potatoes into thin slices.
Place the pumpkin slices in a large baking dish and lightly salt. Place a layer of potatoes on top, lightly salt and pepper. Place the apple slices on top and again potatoes, lightly salt and pepper them again. Spread the coarsely chopped walnuts evenly over the top. Finish with a layer of pumpkin.
Heat the milk with the Gorgonzola in a small saucepan. Melt the Gorgonzola while stirring, add the herbal cream cheese. Season the sauce with the spices to taste and distribute evenly over the contents of the mold. Cook the casserole for 45 minutes at 180 ° C (top / bottom heat).