Slow Cooker French Onion Potatoes Tips, FAQ & printable recipe

Tips for success

To elevate the flavor of this dish even further, consider adding a splash of dry white wine or a splash of Worcestershire sauce to the French onion broth before pouring it over the potatoes.

This adds a bright acidity and a deeper umami undertone that mimics high-end restaurant French onion soup. Additionally, you can toss the potato slices with a tablespoon of all-purpose flour before adding them to the crockpot to help create an even thicker, creamier sauce as they cook.

For the ultimate cheese pull, use a blend of Gruyere and low-moisture mozzarella cheese. While Gruyere provides that classic nutty, sharp flavor, mozzarella adds incredible stretch and meltability.

Always grate the cheese yourself from a block; this small step makes a massive difference in the texture of the melted topping, ensuring a smooth, velvety finish without any graininess from store-bought pre-shredded packages.

Variations

• Garlic Herb Variation: Add minced garlic and chopped fresh rosemary along with the thyme to infuse the broth with rich herb flavor.
• Vegetarian French Onion Potatoes: Ensure the French onion broth is made from a rich vegetable stock base instead of beef broth to make this comforting side dish vegetarian-friendly.

Storage and make-ahead

Fridge

Store in an airtight container in the refrigerator for up to 4 days, cooling for no more than 2 hours beforehand.

Freezer

Freezing is not recommended as the potatoes can become mealy and watery upon thawing.

Reheat

Reheat covered with foil in a 350°F (175°C) oven for 15-20 minutes, or microwave individual portions until hot.

Store any leftover French onion potatoes in an airtight container in the refrigerator for up to three to four days. Allow the dish to cool down to room temperature for no more than two hours before placing it in the fridge to maintain food safety.

To reheat, place individual portions in the microwave or cover the entire dish with foil and heat in a 350 degree Fahrenheit oven until warmed through and the cheese is bubbly.

You can easily prep the components of this dish a day in advance to save time. Caramelize the onions ahead of time and store them in the refrigerator until ready to assemble.

You can also slice the potatoes the night before, but be sure to submerge them in a bowl of cold water in the fridge to prevent them from oxidizing and turning brown; drain and pat them completely dry before layering them in the slow cooker.

Serving ideas

These rich and savory potatoes make an exceptional side dish for a variety of main courses, particularly roasted meats. Serve them alongside a juicy prime rib, roasted chicken, or grilled pork chops to complement the savory onion broth and melted cheese. The rich, gravy-like sauce at the bottom of the crock is perfect for spooning over the meat or dipping crusty French bread into.

For a complete meal, pair these hearty potatoes with a crisp, bright green salad dressed with a simple vinaigrette. The acidity of the salad dressing cuts through the richness of the buttery potatoes and melted Gruyere cheese beautifully. Garnish the potatoes with extra fresh thyme leaves or a sprinkle of chopped fresh parsley right before serving to add a pop of color and freshness.

Frequently asked questions

Recipe card

Slow Cooker French Onion Potatoes

Prep 15 minCook 4 h 5 minRest 10 minTotal 4 h 30 minServes 6

Ingredients

• 3 lb golden potatoes, sliced
• 2 cups caramelized onions, made ahead
• 1 1/2 cups French onion broth
• 1 1/2 cups Gruyere cheese, shredded
• fresh thyme, for serving

Instructions

1. Place the sliced golden potatoes into the slow cooker crock, arranging them in an even layer.
2. Spread the caramelized onions in an even layer over the potatoes. Carefully pour the rich French onion broth around the sides of the slow cooker crock, taking care not to disturb the onions on top of the potatoes.
3. Cover the slow cooker with its lid and cook on high for 3 to 4 hours, or on low for 6 to 8 hours. Avoid lifting the lid during the cooking process to prevent heat and steam from escaping, which can prolong the cooking time.
4. Once the potatoes are fully cooked and tender, remove the lid. Sprinkle the shredded Gruyere cheese in a thick, even layer over the top of the potatoes and caramelized onions, covering them completely from edge to edge.
5. If your slow cooker crock is oven-safe, transfer it uncovered to an oven preheated to broil. Broil for 3 to 5 minutes until the Gruyere cheese is fully melted, bubbling, and beautifully browned in spots. Keep a close eye on it to prevent burning.
6. Carefully remove the hot crockpot from the oven or heating base. Garnish the bubbling casserole with fresh thyme leaves scattered across the top. Let the dish rest for 10 minutes before serving to allow the rich broth to thicken slightly.

Contains: milk

Estimated nutrition per serving

Calories

240

Protein

8 g

Carbohydrates

34 g

Fat

8 g

Fiber

4 g

Sugar

5 g

Sodium

680 mg

Automatic estimate from the ingredient list, not laboratory-verified.