Preheat Oven and Prepare Ingredients : Preheat your oven to 375°F (190°C). Peel and slice the potatoes into thin rounds, slice the mushrooms, chop the onion, and grate or thinly slice the carrots.

Sauté the Vegetables : Warm olive oil in a skillet set over medium heat. Introduce the onions and sauté them until they turn translucent, approximately 3 to 4 minutes. Add the mushrooms and carrots, cooking for another 5-6 minutes until the vegetables are tender. Season with a pinch of salt and pepper, then remove from heat.

Layer the Potatoes and Vegetables : In a spacious baking dish, arrange half of the potato slices in an even layer across the bottom. Spoon half of the sautéed vegetable mixture over the potatoes, spreading it evenly. Layer the remaining potatoes on top, followed by the rest of the vegetable mixture.

Add the Cream and Seasoning : Pour the heavy whipping cream over the layered potatoes and vegetables, allowing it to seep through all the layers. Season with additional salt and pepper, adjusting to your taste.

Bake the Dish : Seal the baking dish with aluminum foil and place it in the preheated oven to bake for 45 to 50 minutes. Remove the foil and continue baking for an additional 15-20 minutes, until the top is golden and the potatoes are tender when pierced with a fork.

Serve and Enjoy : Let the dish cool slightly before serving. This creamy mushroom and potato bake is best enjoyed warm and pairs well with a crisp side salad or protein of choice.