If you’ve ever ordered the potatoes au gratin at Ruth’s Chris and wished you could pull off the same thing at home, this copycat version is for you. The flavor is familiar and comforting, but the method is streamlined so you don’t need a steakhouse kitchen to get it right. We’re sticking with the classic creamy, cheesy, potato base and giving it a modern, weeknight-friendly twist.
Instead of layering raw slices and hoping they cook through, this recipe simmers diced potatoes directly in the cream mixture so they soften evenly and soak up flavor fast. A three-cheese blend, a quick broil, and you get that same bubbly, browned top without any fuss. If you want steakhouse-style potatoes au gratin without overcomplicating dinner, this version earns a spot in your regular rotation.
Simple Steps to Copycat Ruth’s Chris Potatoes Au Gratin
Gathering Your Ingredients
- 6 tablespoons salted butter
- 1 cup thinly sliced yellow onion
- 4 garlic cloves, peeled and minced
- 3 tablespoons all-purpose flour
- 1 cup vegetable broth
- 1 ½ cups light table cream
- 1 ½ pounds russet potatoes, peeled and diced
- 2 cups shredded cheddar, divided
- 1 cup shredded provolone, divided
- ½ cup grated Parmesan, divided
- 1 teaspoon salt
- ¼ teaspoon black pepper
- 2 tablespoons chopped fresh parsley
Mindful Cooking, Step by Step
- Set a large pot over medium heat and add the butter. Allow it to melt completely and start to foam gently, but don’t let it brown.
- Stir in the sliced onion and minced garlic. Cook for about 2 minutes, stirring often, until the onion softens slightly and the garlic is fragrant but not browned.
- Sprinkle the flour evenly over the onions and garlic. Stir continuously to form a smooth paste (roux). Cook for about 1 minute; the mixture should look thick and paste-like, not dry or crumbly.
- Slowly pour in the vegetable broth and light cream while whisking. Keep whisking until the roux is fully blended and no flour lumps remain. Bring the mixture to a gentle simmer; it should start to thicken slightly.
- Add the diced russet potatoes to the pot and stir to coat them in the sauce. Maintain a low simmer and cook for about 20 minutes, stirring occasionally so nothing sticks. The potatoes are ready when you can easily pierce them with a fork but they still hold their shape.
- Remove the pot from the heat. Add 1 cup of cheddar, ½ cup of provolone, and ¼ cup of Parmesan. Gently stir until the cheese is fully melted and the sauce is smooth and creamy. If you see strings or clumps, keep stirring off the heat until it evens out.
- Season the mixture with the salt and black pepper, tasting and adjusting if needed. The sauce should be well seasoned now, as it won’t gain much salt later.
- Set your oven to the low broil setting and allow it to preheat. Position an oven rack in the upper third of the oven, but not too close to the broiler element to avoid burning the cheese.
- Transfer the potato mixture to a casserole dish and spread it into an even layer so it browns uniformly under the broiler.
- Sprinkle the top with the remaining cheddar, provolone, and Parmesan. Try to cover the surface evenly so there are no bare patches.
- Place the casserole under the broiler for 5 to 8 minutes, watching closely. It’s done when the cheese is melted, bubbling around the edges, and lightly golden in spots. If it’s browning too quickly, move the dish to a lower rack.
- Carefully remove the dish from the oven and let it sit for a few minutes so the sauce thickens slightly. Garnish with chopped fresh parsley right before serving for color and freshness.
Getting the Cheese Just Right
The cheese blend is what makes this copycat Ruth’s Chris potatoes au gratin feel restaurant-quality, so it’s worth a bit of attention. Use freshly shredded cheddar, provolone, and Parmesan if possible; pre-shredded cheese often contains anti-caking agents that can make the sauce grainy instead of silky. Finely shredding the cheese helps it melt faster and more evenly into the hot potatoes and cream.
When you stir the cheese into the hot mixture, take the pot off the heat first. Direct high heat can cause the cheese to separate or turn oily. Add the cheese in small handfuls, stirring between each addition until it’s completely melted before adding more. If the mixture looks too thick, you can loosen it with a splash of warm broth or cream. Aim for a sauce that slowly coats the back of a spoon — thick but still pourable — so it stays creamy after baking and broiling.
Broiling for a Golden Top
That signature steakhouse look comes from a controlled broil, not a long bake. The potatoes are already fully cooked on the stovetop, so the oven’s job is just to melt and brown the cheese on top. Preheating the broiler and positioning the rack in the upper third of the oven are key steps. This gives you fast, even browning without overcooking the sauce underneath.
Keep a close eye on the dish once it’s under the broiler. The difference between perfectly golden and burnt can be just a minute. Check at the 4–5 minute mark, then every minute after. If some spots are browning faster than others, you can rotate the dish for more even color. Letting the casserole rest a few minutes after broiling is important; it allows the bubbling sauce to settle and thicken slightly so each scoop holds together instead of running all over the plate.
Recipe Help: Frequently Asked Questions
Can I make these potatoes au gratin ahead of time and reheat them?
Yes, you can prepare this copycat Ruth’s Chris potatoes au gratin in advance, but the timing matters. Make the recipe through the step where you transfer the potato mixture to the casserole dish and top it with cheese, then cover and refrigerate once it cools slightly. When ready to serve, bake at 350°F (rather than broil) until the center is hot and the cheese is melted, then switch to broil for a couple of minutes to brown the top. Avoid broiling straight from cold, as the center may stay cool while the top burns.
Why are my potatoes still firm after simmering for 20 minutes?
If your potatoes are still firm, it’s usually due to either the size of the dice or the heat level. Larger potato chunks need more time, even in hot cream. Make sure you’re dicing the russets into small, even pieces — about ½-inch cubes — so they cook consistently. Also confirm you have a steady, gentle simmer, not just a barely warm pot. If needed, continue cooking for another 5–10 minutes, stirring occasionally and checking doneness with a fork. Don’t add extra flour at this stage; the sauce will naturally thicken as the potatoes finish cooking.
Can I lighten this recipe without losing the creamy texture?
You can reduce the richness slightly, but there are a few smart ways to do it without sacrificing the creamy result. Swap part of the light table cream for whole milk, not skim, as very low-fat milk can make the sauce thin and more likely to curdle. Using a sharp cheddar also boosts flavor, so you may be able to use a bit less cheese overall while still tasting cheesy. Avoid cutting all the fat at once; adjust one element at a time and keep the cooking method the same so the potatoes still cook properly in the sauce and the texture stays smooth.
Copycat Ruth's Chris Potatoes Au Gratin
Equipment
- Large pot
- whisk
- casserole dish
- oven (broil setting)
Ingredients
- 6 tablespoons salted butter
- 1 cup yellow onion thinly sliced
- 4 cloves garlic peeled and minced
- 3 tablespoons all-purpose flour
- 1 cup vegetable broth
- 1 1/2 cups light table cream
- 1 1/2 pounds russet potatoes peeled and diced
- 2 cups shredded cheddar divided
- 1 cup shredded provolone divided
- 1/2 cup grated Parmesan divided
- 1 teaspoon salt
- 1/4 teaspoon black pepper
- 2 tablespoons fresh parsley chopped
Instructions
- Melt the butter in a large pot set over medium heat.
- Add the sliced onion and minced garlic to the melted butter and cook, stirring, until the onion softens, about 2 minutes.
- Sprinkle in the flour and stir constantly for about 1 minute to cook off the raw taste and form a light roux.
- Slowly whisk in the vegetable broth and cream until smooth, then bring the mixture to a gentle simmer.
- Stir in the diced potatoes, reduce the heat if needed, and simmer—stirring occasionally—until the potatoes are tender, about 20 minutes.
- Remove the pot from the heat and fold in 1 cup of cheddar, 1/2 cup of provolone, and 1/4 cup of Parmesan until the cheeses melt into the sauce.
- Taste and season the mixture with the salt and black pepper.
- Set your oven to the low broil setting.
- Transfer the potato and cheese mixture into a prepared casserole dish and smooth it into an even layer.
- Scatter the remaining cheddar, provolone, and Parmesan evenly over the top.
- Place the dish under the broiler and cook for 5 to 8 minutes, watching carefully, until the top is melted, bubbling, and lightly browned.
- Remove from the oven and sprinkle with chopped parsley before serving.