These Copycat Ruth’s Chris Potatoes Au Gratin are creamy, cheesy, and perfectly golden on top—just like the ones you get at the restaurant. Thinly sliced potatoes are layered with a rich mix of cheese, cream, and a hint of garlic, then baked until bubbly and mouth-wateringly delicious.
I love making this recipe when I want to treat myself or impress guests without spending forever in the kitchen. The secret is using good-quality cheese and not skimping on the cream, which keeps the potatoes so tender and flavorful. I always sneak a little extra cheese on top because, well, cheese makes everything better!
This dish is one of those comforting classics that pairs wonderfully with steak or roasted chicken, but honestly, I’m happy to eat it all on its own. It’s a crowd-pleaser at holiday dinners or family gatherings, and whenever I serve it, someone always asks for seconds. Trust me, once you try these potatoes, they’ll become a favorite in your recipe box too.
Key Ingredients & Substitutions
Yukon Gold Potatoes: These have a buttery flavor and hold their shape well. If you can’t find them, Russets work but may be a bit fluffier.
Heavy Cream & Milk: Heavy cream gives richness and creaminess. For a lighter dish, swap heavy cream with half-and-half or use all milk, but expect less richness.
Cheese: Sharp white Cheddar adds flavor depth, while Parmesan gives a nice salty bite. You can substitute Cheddar with Gruyère or Fontina for a nuttier taste.
Garlic & Thyme: Minced garlic flavors the cream, and thyme adds a subtle herbal note. Feel free to skip thyme or try fresh rosemary for a twist.
Butter: Dotting butter on top helps create that lovely golden crust. You can use salted butter but reduce added salt slightly.
How Do You Get Those Perfectly Thin Potato Slices?
Thin slices are key for creamy, tender potatoes that cook evenly. Here’s how to slice them thinly and uniformly:
- Use a sharp knife or a mandoline slicer for best results. A mandoline is faster and ensures even thickness.
- Aim for about 1/8-inch thick slices. Too thick means undercooked potatoes; too thin can turn mushy.
- Work carefully with a mandoline, using a guard to protect your fingers—it’s better to be safe.
- If slicing by hand, steady your knife and cut slowly for consistent slices.
Even slices ensure each layer cooks equally, so your gratin has a smooth, creamy texture throughout. Trust me, this step makes all the difference!
Equipment You’ll Need
- Mandoline slicer or sharp knife – I recommend a mandoline because it slices very thin and even, making the process easier.
- 9×13-inch baking dish or similar size – this gives enough room for layering and baking evenly.
- Medium saucepan – for warming the cream mixture without boiling.
- Mixing spoon or whisk – to stir the cream and cheese mixture smoothly.
- Aluminum foil – to cover the dish for the first part of baking and help the potatoes cook tenderly.
Flavor Variations & Add-Ins
- Swap Cheddar for Gruyère or Fontina for a nuttier, richer flavor.
- Add cooked, crumbled bacon or diced ham between layers for a meaty twist.
- Mix in sautéed mushrooms or caramelized onions for extra flavor and texture.
- Use fresh herbs like thyme or rosemary instead of dried thyme for a brighter herb flavor.
Copycat Ruth’s Chris Potatoes Au Gratin
Ingredients You’ll Need:
Main Ingredients:
- 3 pounds Yukon Gold potatoes, peeled and very thinly sliced
- 2 cups heavy cream
- 1 cup whole milk
- 3 cloves garlic, minced
- 2 teaspoons salt
- 1 teaspoon freshly ground black pepper
- ½ teaspoon dried thyme (optional)
- 2 cups shredded sharp white Cheddar cheese
- 1 cup shredded Parmesan cheese
- 4 tablespoons unsalted butter, cubed (for dotting on top)
How Much Time Will You Need?
This dish takes about 15 minutes of prep time to slice the potatoes and warm the cream mixture. Then, it needs about 1 hour and 20-30 minutes of baking time. After baking, allow 10 minutes of resting time before serving. Plan for roughly 1 hour and 45 minutes total, making it a perfect recipe for a leisurely meal or special occasion.
Step-by-Step Instructions:
1. Get Your Oven and Dish Ready:
Preheat your oven to 350°F (175°C). Butter a 9×13-inch baking dish or use smaller ramekins if you prefer individual servings. This helps prevent sticking and adds delicious buttery flavor.
2. Warm the Cream Mixture:
In a medium saucepan, combine the heavy cream, whole milk, minced garlic, salt, black pepper, and dried thyme if you’re using it. Heat over medium heat just until the mixture is warm and fragrant, but do not let it boil—this takes about 5 minutes.
3. Layer the Potatoes and Cheese:
Arrange a layer of thinly sliced potatoes at the bottom of your prepared dish. Sprinkle some of the shredded Cheddar and Parmesan cheeses evenly over the potatoes. Pour a small amount of the warm cream mixture over the cheese and potatoes to keep everything moist. Repeat this layering process—potatoes, cheese, cream—until all ingredients are used, finishing with cheese on top.
4. Add Butter and Bake:
Dot the top layer with the cubes of unsalted butter, which will help make the top golden and flavorful. Cover the dish tightly with aluminum foil and bake for about 1 hour.
5. Finish Baking and Serve:
Remove the foil and bake for an additional 20 to 30 minutes, or until the potatoes are tender when pierced with a fork and the top is beautifully golden and bubbling. Let the gratin rest for about 10 minutes before serving, allowing the creamy sauce to thicken up just right.
Can I Use Frozen Potatoes for This Recipe?
It’s best to use fresh Yukon Gold potatoes for this gratin to ensure the perfect texture and flavor. If you only have frozen sliced potatoes, thaw them completely and pat dry before using, but the dish might be a bit more watery.
Can I Make Potatoes Au Gratin Ahead of Time?
Yes! You can assemble the dish up to a day in advance. Cover it tightly and keep it refrigerated. When ready, bake covered for the full time plus an extra 10-15 minutes uncovered to get that golden top.
How Should I Store Leftovers?
Store any leftovers in an airtight container in the fridge for up to 3 days. Reheat gently in the oven at 325°F until warmed through to keep the creamy texture.
Can I Substitute Other Cheeses?
Absolutely! Gruyère, Fontina, or Monterey Jack all work well and add different flavor profiles. Just use about the same amount in total and feel free to experiment.