French Onion Potatoes combine the deep, savory flavors of classic French onion soup with tender baked potato slices in a creamy, cheesy casserole. Layered with sour cream, butter, and onion seasoning, then finished with melted cheddar, this comforting side dish is rich, satisfying, and perfect for family dinners or holiday gatherings.

Why You’ll Love This Recipe

• Ultimate Comfort Food – Creamy potatoes and melted cheese create a rich, indulgent texture.
• Big Onion Flavor – French onion soup mix infuses every layer with savory depth.
• Perfect Make-Ahead Side – Assemble in advance and bake when ready to serve.
• Crowd-Pleasing Classic – A reliable favorite for holidays, potlucks, and Sunday dinners.
• Simple Pantry Ingredients – Uses accessible, budget-friendly staples.
• Golden, Bubbly Finish – Uncovered baking at the end ensures a beautifully browned top.

Ingredients You’ll Need

Produce

• 6 medium potatoes, peeled and thinly sliced – Form the hearty base; thin slicing ensures even cooking.

Dairy

• 2 cups sour cream – Provides tangy richness and creamy texture.
• 2 cups shredded cheddar cheese – Melts into a golden, savory topping.
• ½ cup butter, melted – Adds richness and helps coat the potatoes evenly.
• ¼ cup milk – Thins the mixture slightly for smooth distribution.

Seasoning

• 1 packet French onion soup mix – Delivers concentrated onion flavor and seasoning.
• Salt and pepper, to taste – Enhances and balances the creamy components.

Step-by-Step Instructions

Preheat and Prepare the Dish
Preheat the oven to 350°F (175°C). Grease a 9×13-inch baking dish to prevent sticking.

Mix the Creamy Base
In a large bowl, combine sour cream, milk, melted butter, and French onion soup mix. Stir until smooth and fully incorporated.

Layer the Potatoes
Arrange the thinly sliced potatoes evenly in the baking dish, spreading them out in a consistent layer for even cooking.

Add the Cream Mixture
Pour the creamy onion mixture over the potatoes, ensuring all slices are thoroughly coated.

Bake Covered
Cover tightly with aluminum foil and bake for 45 minutes, allowing the potatoes to soften and absorb flavor.

Add Cheese and Finish Baking
Remove the foil, sprinkle shredded cheddar evenly over the top, and bake uncovered for an additional 15 minutes until golden and bubbly.

Rest Before Serving
Let the casserole sit for 5–10 minutes to allow the sauce to thicken slightly before serving.

Recipe Notes & Tips

• Slice Evenly – Use a mandoline for consistent thin slices (about ⅛-inch thick).
• Avoid Overcrowding – Spread potatoes evenly for uniform cooking.
• Check Doneness – Insert a fork to ensure potatoes are tender before adding cheese.
• Add Extra Depth – A pinch of thyme or caramelized onions enhances flavor.
• Use Freshly Shredded Cheese – It melts more smoothly than pre-shredded varieties.
• Let It Rest – Cooling briefly allows the sauce to set for cleaner slices.

Nutritional Information

Prep Time: 15 minutes (approximate based on slicing and prep)
Cook Time: 1 hour
Total Time: 1 hour 15 minutes
Servings: 6
Calories: Approximately 390 per serving (based on provided data; may vary by ingredient brand)

Perfect Pairings

• Roasted chicken or turkey
• Grilled steak or pork chops
• Crisp green salad with vinaigrette
• Steamed green beans or roasted asparagus

Ideal Occasions

• Holiday dinners
• Potluck gatherings
• Sunday family meals
• Comfort-food weeknights

Storage & Serving Tips

• Refrigerate leftovers in an airtight container for up to 4 days.
• Reheat in a 350°F oven for best texture.
• Avoid microwaving if possible to preserve the creamy consistency.
• Freezing is not recommended as dairy may separate.

Creative Variations to Try

• Gruyère Upgrade – Swap cheddar for Gruyère for authentic French onion flavor.
• Add Caramelized Onions – Stir in sautéed onions for extra richness.
• Crispy Topping – Add buttered breadcrumbs during the final bake.
• Herb-Infused Version – Add fresh thyme or rosemary to the cream mixture.

Troubleshooting Common Issues

• Potatoes Still Firm – Bake covered 10–15 minutes longer before adding cheese.
• Watery Sauce – Ensure potatoes are evenly sliced and not too thick.
• Overly Salty Flavor – Reduce added salt since soup mix already contains sodium.
• Cheese Burning Too Quickly – Lower oven temperature slightly or tent loosely with foil.

Why This Recipe Works

This recipe works because it balances starch, fat, and seasoning effectively. Thinly sliced potatoes cook evenly and absorb the savory onion-infused cream mixture. Sour cream and butter provide richness, while the French onion soup mix delivers concentrated umami and depth. Covering the dish traps steam, allowing the potatoes to soften thoroughly before finishing uncovered for browning and flavor concentration. At around 390 calories per serving, it’s indulgent yet portion-controlled for a satisfying side dish.

Final Thoughts

French Onion Potatoes are the kind of side dish that steals the spotlight. Creamy, cheesy, and packed with savory onion flavor, they pair beautifully with a variety of main courses. For a lighter variation, reduce butter slightly or substitute part of the sour cream with Greek yogurt. Whether for holidays or cozy dinners, this dish delivers comforting flavor every time.