Cook potatoes in the skin and peel them. (I speed up cooking time with my a pressure cooker)
Wash zucchini and remove shaft and flower.
Now cut potatoes and zucchini in 1/2 cm slices, layer them in a casserole form, alternately imbricate.
Season the vegetables with some salt and cayenne pepper.
Pour sour cream in a small bowl and add 2-3 tablespoons of water. Peel the garlic cloves, force them through a garlic press and mix the crushed garlic with the liquid.
Now pour the sauce over your vegetables.
At last, sprinkle the ground cheese on the top.
Bake the zucchini potato casserole in a preheated oven at 190°C /374°F approx. 30 minutes.
When ready, the cheese should look golden yellow.
Season with salt and pepper.
Notes
To save on fat, I use only 200 ml sour cream and replace the other 200ml with low-fat milk.