The Creamy, Earthy Side Dish That Deserves the Spotlight
Introduction: A Dish That Marries Earthy Comfort with Gourmet Elegance
There’s something irresistibly comforting about the creamy, golden layers of a well-made gratin. Add the umami depth of mushrooms, the sharp bite of Gorgonzola cheese, and the rustic heartiness of thinly sliced potatoes, and you’ve got a show-stopping dish that’s both indulgent and memorable.
This Potato and Mushroom Gratin recipe is more than just a side — it’s a celebration of earthy, creamy, cheesy goodness. Whether served with a perfectly cooked filet mignon, roasted chicken, or enjoyed as a standalone vegetarian main course, this potato mushroom bake delivers a satisfying, soul-warming experience.
If you’re searching for new mushroom dishes to expand your recipe collection, especially those that feature bold flavors and gourmet appeal, this is one to bookmark, pin, and come back to often.
What Makes This Gratin Special?
Unlike your average gratin, which may rely solely on cream and cheese, this version adds a layer of complexity through sautéed mushrooms and caramelized onions. The rich, tangy Gorgonzola mushrooms lift the entire dish, transforming it from simple comfort food to a restaurant-quality experience.
Key Features:
- Bold, Earthy Flavor: Mushrooms and Gorgonzola are a match made in culinary heaven.
- Luxuriously Creamy Texture: Thanks to a homemade cheese sauce and thin-sliced potatoes.
- Impressive Presentation: Golden on top, lusciously creamy beneath, and dotted with herbs.
- Great Pairing: A natural complement to filet mignon with potato gratin or roasted meats.
Ingredients: Building the Ultimate Gratin
🧅 For the Mushroom and Onion Mixture:
- 2 tbsp olive oil
- 1 tbsp unsalted butter
- 1 large yellow onion, thinly sliced
- 4 cloves garlic, minced
- 500g (1 lb) mushrooms, sliced (cremini, white button, or a mix)
- 1 tbsp fresh thyme (or 1 tsp dried thyme)
- Salt and pepper, to taste
🥔 For the Potatoes:
- 4 large russet potatoes, peeled and thinly sliced (about 2 lbs)
- Optional: Mandoline slicer for even, thin slices
🧀 For the Cheese Sauce:
- 2 tbsp unsalted butter
- 2 tbsp all-purpose flour
- 2 cups whole milk or half-and-half
- 100g (3.5 oz) Gorgonzola cheese, crumbled
- ½ cup grated Parmesan cheese
- ½ tsp sea salt
- ¼ tsp nutmeg (optional)
- Freshly ground black pepper, to taste
🍽️ For the Topping:
- ⅓ cup grated Gruyère or mozzarella
- Fresh parsley, chopped (for garnish)
How to Make Potato and Mushroom Gratin: Step-by-Step
Step 1: Sauté the Mushroom and Onion Mixture
- Heat olive oil and butter in a large skillet over medium heat.
- Add the sliced onion and cook until golden and caramelized, about 8 minutes.
- Stir in garlic, then add mushrooms and thyme. Season with salt and pepper.
- Sauté for 10–12 minutes, until mushrooms are deeply browned and moisture has evaporated.
Pro Tip: Don’t crowd the mushrooms! Give them space to brown instead of steam.
This forms the flavorful foundation of your mushroom and onion gratin layer.
Step 2: Prepare the Gorgonzola Cheese Sauce
- In a saucepan, melt butter over medium heat.
- Add flour and whisk to form a roux; cook for 1–2 minutes.
- Gradually whisk in milk and cook until thickened.
- Reduce heat to low, stir in Gorgonzola and Parmesan until smooth.
- Add salt, pepper, and optional nutmeg.
This sauce adds decadence to your cheese herb potato gratin, with that unmistakable blue cheese flair from the Gorgonzola cheese.
Step 3: Assemble the Gratin
- Preheat oven to 375°F (190°C).
- Grease a 9×13-inch baking dish with butter or oil.
- Layer half the potato slices evenly on the bottom.
- Spread half the mushroom and onion mixture on top.
- Pour over half the cheese sauce.
- Repeat with remaining potatoes, mushrooms, and cheese sauce.
- Sprinkle with grated Gruyère or mozzarella if using.
Step 4: Bake to Golden Perfection
- Cover dish tightly with foil.
- Bake for 40 minutes covered.
- Uncover and bake an additional 20–25 minutes until golden, bubbly, and crispy on top.
- Let rest for 10 minutes before serving.
- Garnish with chopped parsley.
Flavor Variations: Make It Your Own
Swap the Cheese:
- Use Fontina, Brie, or goat cheese for different flavor profiles.
- Add a smoky twist with smoked gouda or sharp cheddar.
Add Protein:
- Stir in bacon, pancetta, or chopped ham for a meatier gratin.
- For a vegetarian protein boost, try white beans or lentils in the mushroom layer.
Herbs & Spices:
- Add rosemary, sage, or tarragon for extra depth.
- A touch of white truffle oil before baking takes this dish over the top.
What to Serve With Potato and Mushroom Gratin
This potato mushroom bake shines as both a side and a main. Try these serving ideas:
🍖 Filet Mignon With Potato Gratin:
Serve with seared or grilled filet mignon. The creamy, earthy gratin balances the richness of the beef perfectly. Add a glass of red wine, and you have an elegant, restaurant-worthy dinner.
🐓 Roast Chicken or Turkey:
Roasted poultry gets a serious upgrade with this gratin on the side. It’s especially delicious as a holiday side dish with turkey or duck.
🥗 Light Salad:
Balance the richness with a crisp salad of arugula, lemon vinaigrette, and shaved fennel.
🥖 Rustic Bread:
Mop up the creamy cheese sauce with slices of crusty sourdough or rosemary focaccia.
Storage and Make-Ahead Tips
🧊 Make Ahead:
- Assemble the entire dish, cover, and refrigerate for up to 24 hours before baking.
- Bring to room temperature before placing in the oven.
❄️ Freeze:
- Cool completely and freeze individual portions.
- Reheat in oven at 350°F (175°C) for 15–20 minutes until hot.
🍽️ Leftovers:
- Store in an airtight container in the fridge for up to 4 days.
- Reheat gently in the oven or microwave.
Nutrition Information (Approximate Per Serving)
Based on 8 servings:
- Calories: 355
- Fat: 23g
- Saturated Fat: 13g
- Carbohydrates: 27g
- Protein: 10g
- Fiber: 3g
- Sodium: 480mg
- Calcium: 225mg
Spotlight Ingredient: Gorgonzola Cheese
Gorgonzola is a type of Italian blue cheese known for its creamy texture and bold, slightly spicy flavor. There are two main types:
- Gorgonzola Dolce (sweet, creamy)
- Gorgonzola Piccante (stronger, aged)
For this gratin, Gorgonzola Dolce is preferred — it melts smoothly into sauces, creating a luxurious texture without overpowering the dish.
This cheese is especially wonderful with mushroom dishes, as the earthy fungi and pungent cheese bring out the best in each other. The result? A Gorgonzola mushroom blend that’s bold yet balanced.
FAQs About Potato and Mushroom Gratin
Can I use other mushrooms?
Absolutely. Try shiitake, portobello, oyster, or a wild mushroom mix. Each brings its own texture and flavor.
Can I make it without cheese?
You can omit Gorgonzola for a dairy-free version and use plant-based milk with a roux for the sauce. Nutritional yeast adds cheesy flavor without dairy.
What if I don’t like blue cheese?
Swap in goat cheese, cream cheese, or even ricotta. You’ll still get creaminess without the sharpness of Gorgonzola.
Can I make this gluten-free?
Yes! Use gluten-free flour for the roux and double-check that your cheeses are gluten-free.
Why This Gratin Belongs On Your Table
From weeknight meals to special occasions, this Potato and Mushroom Gratin delivers a mix of comfort and class. Its layers of buttery potatoes, caramelized onions, sautéed mushrooms, and creamy Gorgonzola cheese elevate it to more than just another casserole — it’s a dish to be remembered.
Whether you’re serving filet mignon with potato gratin or building your best-ever vegetarian holiday spread, this dish is a star. It’s hearty enough to satisfy, elegant enough to impress, and flexible enough to adapt to your taste.
