Delicious Homemade Au Gratin Potatoes

If you’re looking for a comforting and hearty side dish, look no further than homemade au gratin potatoes.

This classic recipe combines thinly sliced potatoes with a rich, cheesy sauce that’s baked to golden perfection. Whether you’re hosting a family dinner or just craving something warm and satisfying, these au gratin potatoes are sure to hit the spot.

Ingredients

Equipment Needed:

• Mandolin (optional): Not necessary, but super helpful for slicing potatoes evenly.

Ingredients:

• 3 lbs Yukon gold potatoes (about 6 medium potatoes)
• 1 medium white onion, thinly sliced
• 2 tbsp unsalted butter
• ¼ cup flour
• 1½ cups whole milk (or unsweetened almond milk)
• 8 oz sharp cheddar cheese, shredded and divided in half (avoid pre-shredded)
• ½ tsp garlic powder
• 1 tsp Dijon mustard
• ½ tsp MSG (optional)
• 1 tsp freshly ground black pepper
• Salt to taste
• ½ cup freshly grated Parmesan cheese

Instructions

1. Preheat and Prep: Preheat your oven to 375°F. Grease a 2-quart (8 x 10-inch) baking dish with butter or oil to prevent sticking.
2. Slice the Potatoes and Onions: Using a mandolin or a sharp knife, thinly slice the potatoes into ⅛-inch rounds. Thinly slice the white onion as well.
3. Assemble the Dish: Arrange the sliced potatoes in three tight, slanted rows in the prepared baking dish. Leave enough space to insert onion slices between the potatoes throughout the dish.
4. Prepare the Cheese Sauce:
   • Heat a medium-sized saucepan over medium heat.
   • Add the unsalted butter. Once melted, whisk in the flour to create a roux.
   • Slowly pour in the milk, whisking continuously to eliminate any lumps.
   • Bring the mixture to a low simmer until it reaches a gravy-like consistency.
   • Reduce the heat to low and stir in half of the shredded sharp cheddar cheese.
   • Add the garlic powder, Dijon mustard, MSG (if using), freshly ground black pepper, and salt. If the sauce is too thick, add ¼ cup of water.
   • Taste the sauce and adjust the salt as needed. It should be slightly on the salty side, as the potatoes will absorb some of the seasoning.
5. Combine and Bake:
   • Pour the cheese sauce evenly over the potatoes and onions, making sure everything is well-covered.
   • Cover the baking dish with aluminum foil and bake for 45 minutes.
6. Add More Cheese and Finish Baking:
   • After 45 minutes, remove the foil.
   • Sprinkle the remaining shredded cheddar and the freshly grated Parmesan cheese over the top.
   • Return the dish to the oven and bake uncovered for an additional 30 to 45 minutes, or until the potatoes are tender and the top is golden brown.
7. Serve:
   • Remove from the oven and let it sit for a few minutes to set.
   • Serve warm and enjoy!

What Is the Difference Between Scalloped Potatoes and Au Gratin?

While both dishes are delicious and feature layered potatoes baked in a creamy sauce, there are key differences between scalloped potatoes and au gratin potatoes:

• Cheese Content:
  • Scalloped Potatoes: Traditionally made without cheese. The sauce is usually a simple cream or milk-based mixture seasoned with herbs and spices.
  • Au Gratin Potatoes: Cheese is a defining ingredient. The dish is layered with cheese and often topped with breadcrumbs for a crispy crust.
• Potato Preparation:
  • Scalloped Potatoes: Potatoes are cut slightly thicker and the layers are more distinct.
  • Au Gratin Potatoes: Potatoes are sliced thinner, allowing them to cook more evenly with the cheese and sauce.
• Topping:
  • Scalloped Potatoes: Generally doesn’t include a topping.
  • Au Gratin Potatoes: Often topped with cheese and sometimes breadcrumbs to create a gratinéed, or browned, crust.

What Makes Something Au Gratin?

The term “au gratin” refers to a dish that is topped with a browned crust, typically made from breadcrumbs, grated cheese, egg, or butter. The key elements that make a dish au gratin are:

• Gratinée Technique:
  • The dish is baked or broiled until the topping is crispy and golden brown.
• Cheese or Breadcrumbs:
  • A generous amount of cheese or breadcrumbs is used to create the crusty top layer.
• Baking Dish:
  • Traditionally prepared in a shallow baking dish to maximize the surface area for browning.

Why Is It Called Au Gratin?

The term “au gratin” originates from the French language:

• “Gratin”:
  • A French culinary technique that involves topping a dish with a browned crust.
• Etymology:
  • The word comes from the French verb “gratter,” meaning “to scrape” or “to grate,” referring to the grated cheese or breadcrumbs used in the dish.
• Culinary Tradition:
  • The technique was developed to add texture and enhance the overall dining experience by introducing a crunchy element to soft, baked dishes.

What Else Can I Serve With This?

Au gratin potatoes are a versatile side dish that pairs well with a variety of main courses:

• Roasted Meats:
  • Beef roast, grilled steak, or roasted chicken complement the rich cheesiness of the potatoes.
• Grilled Fish:
  • A simple grilled salmon or white fish can balance the heaviness of the dish.
• Vegetables:
  • Steamed or roasted vegetables like asparagus, green beans, or broccoli add a fresh element.
• Salads:
  • A crisp green salad with a light vinaigrette can provide a refreshing contrast.
• Bread:
  • Warm rolls or crusty baguettes are great for sopping up any leftover cheese sauce.

Storage Instructions

If you have leftovers or want to prepare the dish in advance, follow these storage tips:

• Refrigeration:
  • Allow the dish to cool to room temperature.
  • Cover tightly with plastic wrap or transfer to an airtight container.
  • Store in the refrigerator for up to 3-4 days.
• Reheating:
  • Preheat the oven to 350°F.
  • Place the potatoes in an oven-safe dish and cover with foil.
  • Heat for about 20-25 minutes, or until warmed through.
• Freezing:
  • It’s possible to freeze au gratin potatoes, but the texture may change slightly.
  • Wrap the cooled dish tightly in plastic wrap and then aluminum foil.
  • Freeze for up to one month.
  • Thaw in the refrigerator overnight before reheating.