1 Preheat the oven to 180°C (approximately 350°F).
2 Peel the onion and garlic, finely dice and sauté in melted butter until translucent. Peel the potatoes, rinse and cut into thin slices. Trim leeks, rinse and cut into rings. Blanch leeks in boiling salted water about 2 minutes, rinse in cold water and drain well.
3 Remove rind from the cheese and cut into small cubes. Mix cheese with the potatoes, leeks and nuts. Season with salt, pepper and nutmeg and divide among 4 oven-proof ramekins.
4 Mix cream with the onion-garlic mixture, milk and eggs and pour over ramekins.
5 Bake in preheated oven until golden brown, about 40 minutes. Serve hot.