Ruth’s Chris Potatoes Au Gratin Copycat Recipe

I reverse-engineered Ruth’s Chris Potatoes Au Gratin to reveal a clever shortcut that recreates the restaurant’s signature browned top using just a few pantry ingredients.

I wasn’t expecting to nail Ruth’s Chris Potatoes au Gratin at home, but after messing around with russet potatoes and melting heaps of Gruyere cheese I kept coming back for more. There’s something almost suspicious about the crust, the way the top browns and the edges get just a bit crisp, like it’s hiding a trick.

I kept tasting and swearing this couldn’t be restaurant level, then it was. If you like Copycat Restaurant Recipes this one will make you do a double take.

I’m not claiming perfection, I messed up a few steps, yet somehow every forkful won me over.

Ingredients

• Potatoes: Starchy base high in carbs and potassium gives creamy texture and hearty bite.
• Heavy cream: Very rich fat it adds silkiness and calories not healthy in large amounts.
• Gruyere cheese: Nutty melty adds protein and calcium gives savory depth to potatoes.
• Parmesan cheese: Sharp salty finish concentrated umami little fat strong flavor punch.
• Butter: Adds richness and mouthfeel mostly saturated fats boosts overall flavor.
• Garlic: Fragrant pungent low calorie brings savory aroma and slight bite.
• Chives or parsley: Fresh herb notes small vitamins and fiber brightens heavy creamy dish.
• Whole milk: Lightens texture supplies calcium and a bit of protein milky sweetness.
• Nutmeg: Warm slightly sweet spice tiny pinch lifts flavors without making sweet.

Ingredient Quantities

• 3 lb russet potatoes
• 2 cups heavy cream
• 1 cup whole milk
• 6 tbsp unsalted butter
• 2 cups Gruyere cheese, shredded (about 8 oz)
• 1/2 cup grated Parmesan cheese (about 2 oz)
• 2 cloves garlic, minced
• 1 1/2 teaspoons kosher salt
• 1/2 teaspoon freshly ground black pepper
• 1/8 teaspoon ground nutmeg
• 2 tbsp chopped fresh chives or parsley (optional)

How to Make this

1. Preheat oven to 375°F and butter a 3-quart or 9×13 baking dish well so the potatoes wont stick.

2. Peel the russets and slice them very thin, about 1/8 inch, with a mandoline or sharp knife; rinse the slices and pat them dry with towels.

3. In a medium saucepan melt the 6 tbsp butter over medium heat, add the 2 minced garlic cloves and cook 20 to 30 seconds until fragrant, then stir in 2 cups heavy cream and 1 cup whole milk.

4. Season the cream with 1 1/2 tsp kosher salt, 1/2 tsp black pepper and 1/8 tsp nutmeg; warm the mixture until tiny bubbles form at the edge but do not boil, then remove from heat.

5. Arrange about a third of the potato slices in an even layer in the dish, sprinkle with a generous handful of the shredded Gruyere and a little grated Parmesan, then repeat to make 2 more layers; save about 1/2 cup of the cheese mixture for the top.

6. Pour the warm cream mixture evenly over the layered potatoes, pressing down gently so the liquid settles between slices.

7. Cover the dish tightly with foil and bake 45 to 55 minutes, until a knife slips into the potatoes with just a little resistance.

8. Remove the foil, sprinkle the reserved Gruyere and Parmesan over the top, then return uncovered and bake another 15 to 20 minutes until cheese is bubbly and golden; if you want a darker top, broil for 1 to 2 minutes while watching closely.

9. Let the gratin rest for about 10 minutes so it sets up a bit, then sprinkle 2 tbsp chopped fresh chives or parsley over the top and serve warm.

Equipment Needed

1. 3-quart (9×13) baking dish, well buttered so the potatoes wont stick
2. Mandoline or a sharp chef’s knife for 1/8 inch slices
3. Vegetable peeler
4. Cutting board
5. Medium saucepan
6. Measuring cups and spoons
7. Box grater or microplane for Gruyere and Parmesan
8. Aluminum foil
9. Oven mitts or pot holders
10. Paper towels or clean kitchen towels for drying slices

FAQ

Ruth’s Chris Potatoes Au Gratin Copycat Recipe Substitutions and Variations

• Russet potatoes: try Yukon Golds or red potatoes. Yukon Golds give a creamier, smoother bite; reds hold their shape better, so you might need to cut slices a bit thinner or shorten bake time.
• Heavy cream: use evaporated milk for a lighter but still rich result, or make a stand-in by mixing whole milk with melted butter (per cup of cream use 3/4 cup milk + 1/4 cup melted butter).
• Gruyere cheese: swap with Emmental, Swiss, or fontina. They melt the same way as Gruyere, flavor will be a little different but still nutty and melty.
• Parmesan cheese: use Pecorino Romano or aged Asiago. Pecorino is saltier and tangier so taste before salting, Asiago is milder but still gives that savory bite.

Pro Tips

– Slice like a boss but be safe. Try to keep every slice the same thickness so they cook evenly, use a mandoline if you have one and the guard or a cut-resistant glove because fingers matter, but if you only have a knife go slow and steady. Rinse the slices to wash off excess starch and pat them very dry, otherwise the gratin can turn out gummy.

– Warm the butter and cream gently, dont rush it. Let the garlic perfume the butter for just a few seconds but dont brown it, heat the cream until tiny bubbles appear at the edge not a rolling boil, and remove from heat right away. If the cream ever looks like it might separate, take it off the heat and give it a stir, youll get a silkier sauce that way.

– Layer without squashing, and choose your dish wisely. Overlap slices a little but dont press them into a solid brick or the cream wont move between layers, and use a metal pan if you want a quicker browning top, glass takes longer. Save the best of the cheese for the finish, cover tight while baking so the potatoes steam then uncover at the end for the golden crust.

– Do ahead and finishing tricks. You can assemble this a few hours or even a day ahead and keep it chilled, but let it sit at room temp for 20 to 30 minutes before baking so it heats more evenly. After baking let it rest long enough to set or it will be soupy, and if you want a super dark top broil for only a minute or two while watching it closely or youll burn it.