Ingredients
250g mushrooms (such as button or cremini), sliced
4 large potatoes, peeled and thinly sliced
1 onion, finely chopped
2 cloves garlic, minced
1/2 cup grated Parmesan cheese
1/4 cup chopped fresh parsley
3 eggs
1/2 cup milk
Salt and pepper to taste
Olive oil or butter for cooking
Instructions
Prepare Potatoes and Mushrooms:
Preheat the oven to 375°F (190°C). Grease a round baking dish or a springform pan with olive oil or butter.
Peel and thinly slice the potatoes, about 1/8 inch thick. Slice the mushrooms.
In a large skillet, heat olive oil over medium heat. Add chopped onion and minced garlic, sauté until softened.
Add sliced mushrooms to the skillet and cook until they release moisture and turn golden brown. Season with salt and pepper. Set aside.
Assemble the Gratin:
Layer sliced potatoes on the bottom of the greased baking dish, slightly overlapping them.
Sprinkle some of the cooked mushrooms and grated Parmesan cheese over the potatoes.
Repeat layers, alternating between potatoes, mushrooms, and cheese, finishing with a layer of potatoes on top.
Prepare Egg Mixture:
In a bowl, whisk together eggs and milk. Season with salt and pepper.
Pour the egg mixture evenly over the layered potatoes and mushrooms.
Bake:
Cover the baking dish with foil and bake in the preheated oven for about 45 minutes.
Remove the foil and bake for an additional 15-20 minutes, or until the top is golden brown and potatoes are tender when pierced with a fork.
Enjoy.