1. Peel the potatoes and cut them into slices with a thickness of about 0.4 inches (1cm). Heat a Dutch oven with salted water and boil the potato slices for about 8 minutes. Drain the potato slices and set aside so they can cool down a bit.

2. Wash and dry the zucchini. Cut them into slices with a thickness of about 0.4 inches (1cm) as well. Layer the potato and zucchini slices alternating in a large casserole dish. Set aside.

3. Peel and finely dice or chop the onion and garlic. Add the butter to a large saucepan, heat up, and melt it. Add the onion and garlic and sauté for a few minutes until soft and glossy. Next, add the flour and sauté briefly with the onion and garlic, then deglaze with the veggie stock and milk. Allow the sauce to thicken while stirring constantly. Add the sour cream and stir in. Season the sauce with dried oregano, cayenne pepper, fresh nutmeg, salt, and pepper.

4. Preheat the oven to 390°F (200°C). Pour the sauce over the potato and zucchini slices, sprinkle everything with cheese, and bake for about 40-45 minutes – the veggies should be cooked through, and the cheese should have a nice golden color. Remove from the oven and let sit for about 10 minutes. Before serving, sprinkle with some chives and serve with additional sour cream (optional).