Lyonnaise Potatoes

Ingredients

• 30 ml (2 tablespoons), dividedavocado oil or another high-heat oil
• 28 g (2 tablespoons), dividedbutter, ideally high-fat European-style butter
• 2 mediumyellow onions or sweet onions, halved from top to bottom and thinly sliced
• to tastekosher salt
• 680 g (1½ pounds)Yukon Gold potatoes or peeled russet potatoes
• to tastefreshly ground black pepper
• 15 g (¼ cup)fresh parsley, finely chopped

Instructions

1. 1

   Cook the onions

   Heat 15 ml (1 tablespoon) of the oil and 14 g (1 tablespoon) of the butter in a large non-stick frying pan over medium heat until sizzling. Add the onions and a generous pinch of salt. Cook, stirring often, for 15–20 minutes, until soft and lightly golden. Take the pan off the heat, transfer the onions to a bowl and set the pan aside without wiping it.

2. 2

   Parboil the potatoes

   Meanwhile, slice the potatoes crosswise into 6 mm (¼-inch) rounds and put them in a medium saucepan. Cover with cold water, add a generous pinch of salt and bring to the boil over medium-high heat. Boil for about 3 minutes, until nearly tender, skimming off foam as needed. Drain and set aside.

3. 3

   Crisp and finish

   Put the same frying pan over medium heat. Add the remaining 15 ml (1 tablespoon) of oil and 14 g (1 tablespoon) of butter and heat until sizzling. Add the parboiled potatoes and cook for 15–18 minutes, gently turning them every 3 minutes so they crisp on both sides. When crisp to your liking and cooked through, return the onions to the pan, season with salt and pepper to taste, and cook and stir for about 2 minutes, until heated through. Transfer to a platter, sprinkle with parsley and serve hot.

What are Lyonnaise potatoes?

Lyonnaise potatoes are a French preparation associated with Lyon: sliced potatoes cooked with onions, traditionally browned in a pan. This version builds flavour by cooking the onions slowly first, then crisping the potatoes in the same pan.

Parboiling helps the potato slices become tender before they spend time browning. The result is a side dish with soft centres, crisp edges and sweet, savoury onion throughout.

Nutrition and macros by portion

The nutrition label shows one serving as written: 270 calories, 4g protein, 36g carbs, 13g fat.

The potatoes provide most of the carbohydrates, while the oil and butter contribute most of the fat. The potatoes and onions provide a little protein, but this is primarily a side dish rather than a protein-rich main. Pair a serving with a protein of your choice and vegetables or salad to round out the plate.

Choose potatoes that hold their shape

Yukon Gold potatoes: their naturally creamy texture suits the tender middle and crisp exterior here. Slice them evenly so they cook at a similar rate.

Russet potatoes: these are also an option, but the recipe specifies peeling them. Handle the parboiled slices gently, as they can be more prone to breaking.

Give the onions time

Slow cooking: the onions need 15–20 minutes over medium heat to soften and turn lightly golden. Stir often and lower the heat if they start colouring too quickly.

Shared pan: keep the cooked onions in a bowl while the potatoes crisp, and leave the pan unwiped. The oil and butter left behind carry flavour into the next stage.

Parboil without overcooking

Thin slices: aim for 6 mm rounds so the potatoes can brown in the time given. A mandoline can help make the slices consistent; use it carefully.

Nearly tender: about 3 minutes in boiling water is the guide, not a cue to cook the slices until fully soft. Drain them once they are just short of tender so they can finish in the frying pan.

Let the potatoes brown

Steady heat: warm the remaining oil and butter until sizzling before adding the drained potatoes. This gives them a chance to brown rather than simply warm through.

Gentle turning: flip the slices about every 3 minutes during the 15–18 minute pan-fry. Turning them carefully helps crisp both sides without breaking the nearly tender potatoes.

Finish with seasoning and parsley

Final seasoning: add the onions back only after the potatoes are crisp and cooked through. Salt and pepper can be adjusted at this point, then 2 minutes in the pan warms everything together.

Fresh parsley: scatter it over the dish just before serving for a fresh, green finish. Serve while hot, when the potato edges are at their crispest.

What to serve alongside

These potatoes work well alongside roast chicken, grilled fish or a simple green salad. Their buttery, crisp texture also makes them a satisfying partner for a plainly cooked main.

If the rest of the meal is rich, add a sharp salad or lightly dressed vegetables for contrast. Serve the potatoes straight from the pan or transfer them to a warmed platter.

Recipe notes & tips

• Slice the potatoes to an even 6 mm thickness so they cook at a similar pace.
• Keep the onions moving as they cook, especially as they start to turn golden.
• Skim the foam from the saucepan during parboiling if it builds up.
• Drain the potatoes well before adding them to the hot frying pan.
• Turn the potato slices gently to help keep them intact.
• Season the dish after returning the onions to the pan, then taste before serving.

Variations

• Use sweet onions: swap them for the yellow onions for a milder onion flavour.
• Try russets: peel the potatoes first, as directed, and turn the slices gently after parboiling.
• Add herbs: replace some or all of the parsley with another finely chopped fresh herb.
• Adjust the pepper: use less for a milder finish or add more freshly ground pepper at the table.
• Serve with greens: add a simple salad alongside for a fresh contrast to the buttery potatoes.

Common mistakes to avoid

• Uneven slices: thick and thin rounds cook at different speeds; aim for consistent 6 mm slices.
• Rushing the onions: they may colour before softening; cook over medium heat and stir often.
• Overboiling the potatoes: fully soft slices can fall apart in the pan; stop when they are nearly tender.
• Adding wet potatoes: excess water can interfere with browning; drain them well before frying.
• Turning too roughly: the slices may break; flip them gently with a spatula.
• Crowding the pan: the slices may not crisp evenly; use a large frying pan so they have room.

How to store

Cool leftovers and refrigerate them in a covered container for up to 3 days. Reheat in a frying pan over medium heat until hot, turning gently; this helps restore some crispness better than reheating in the microwave.

Frequently asked questions