Quick Recipe Version (TL;DR)
Quick Ingredients
- 4 medium russet potatoes, 9 ounces (250 g) each, scrubbed
- 2 tablespoons (30 ml) olive oil
- 4 tablespoons (56 g) unsalted butter
- 6 medium garlic cloves (18 g), finely minced
- 2 teaspoons finely chopped fresh rosemary
- 2 teaspoons fresh thyme leaves
- 3/4 teaspoon (4.5 g) fine sea salt
- 1/2 teaspoon freshly ground black pepper
- 1/2 cup (40 g) finely grated Parmesan cheese
- 1 tablespoon chopped fresh flat-leaf parsley
Do This
- 1. Heat the oven to 425°F (220°C). Line a rimmed metal baking sheet with parchment rated for this temperature.
- 2. Cut each potato crosswise into 1/8-inch (3 mm) slices, leaving the bottom 1/4 inch (6 mm) intact. Rinse between the slices and dry thoroughly.
- 3. Rub with the olive oil, salt, and pepper. Arrange cut-side up and roast for 35 minutes.
- 4. Melt the butter and brush half over and between the slices. Roast for another 25 minutes. Meanwhile, gently cook the garlic, rosemary, and thyme in the remaining butter over low heat for 1 minute; remove from the heat.
- 5. Brush the garlic-herb butter over the potatoes, gently opening the slices. Roast for 10 minutes.
- 6. Sprinkle with Parmesan and roast for 5 minutes, until golden and fork-tender. Finish with parsley and serve immediately.
Why You’ll Love This Recipe
- The best of both textures: Delicately crisp, golden edges surround soft, fluffy potato centers.
- Big flavor from everyday ingredients: Garlic butter, olive oil, woody herbs, and Parmesan make every slice delicious.
- Impressive without being complicated: Two wooden spoon handles help you create the signature accordion shape.
- A versatile side dish: Serve alongside roast chicken, steak, baked fish, or a hearty mushroom main.
Grocery List
- Produce: 4 medium russet potatoes, 1 head of garlic, fresh rosemary, fresh thyme, and flat-leaf parsley.
- Dairy: Unsalted butter and a wedge of Parmesan cheese.
- Pantry: Olive oil, fine sea salt, and black pepper.
Full Ingredients
For the Potatoes
- 4 medium russet potatoes, 9 ounces (250 g) each, about 2 1/4 pounds (1 kg) total
- 2 tablespoons (30 ml) olive oil
- 3/4 teaspoon (4.5 g) fine sea salt
- 1/2 teaspoon freshly ground black pepper
For the Garlic-Herb Butter
- 4 tablespoons (56 g) unsalted butter, divided after melting
- 6 medium garlic cloves (18 g), finely minced
- 2 teaspoons finely chopped fresh rosemary, measured after removing the woody stems
- 2 teaspoons fresh thyme leaves, stripped from their stems
For Finishing
- 1/2 cup (40 g) finely grated Parmesan cheese
- 1 tablespoon chopped fresh flat-leaf parsley
Step-by-Step Instructions
Step 1: Heat the oven and prepare the pan
Heat the oven to 425°F (220°C), conventional setting, with a rack in the middle. Line a rimmed metal baking sheet with parchment paper rated for at least 425°F (220°C), or use the pan unlined. Choose a pan large enough to leave at least 2 inches (5 cm) between the potatoes so hot air can circulate.
Scrub the potatoes well and leave the skins on. Choose potatoes of similar size so they finish cooking together.
Step 2: Make the accordion cuts
Place a potato on a cutting board with a wooden spoon handle along each long side. Using a sharp knife, make crosswise cuts every 1/8 inch (3 mm), stopping before you cut through the bottom. Leave an intact base about 1/4 inch (6 mm) thick so the slices stay connected.
The spoon handles act as a guide, but use extra care at the tapered ends, where the knife may pass below the guides. Repeat with the remaining potatoes. Briefly rinse each potato under cold running water, gently easing the cuts apart to wash away some surface starch. Pat very dry, including between the slices as much as possible.
Step 3: Season and start roasting
Rub the potatoes all over with the 2 tablespoons olive oil, including the undersides. Gently work a little oil into the cuts without forcing them open. Sprinkle evenly with the salt and pepper.
Set the potatoes cut-side up on the prepared pan. Roast for 35 minutes. The skins will begin to crisp, and the slices will start to separate.
Step 4: Brush with butter and continue roasting
Near the end of the first roasting stage, melt the 4 tablespoons butter in a small saucepan over low heat. Transfer half of the melted butter, approximately 2 tablespoons, to a small bowl.
Remove the potatoes from the oven and brush that plain melted butter over the tops and into the newly opened gaps. A pastry brush works well; use a spoon to drizzle butter into any deeper openings. Return the potatoes to the oven for 25 minutes.
Step 5: Make the garlic-herb butter
While the potatoes continue roasting, add the minced garlic, rosemary, and thyme to the remaining 2 tablespoons melted butter in the saucepan. Cook over low heat for 1 minute, stirring, just until fragrant. Do not let the garlic brown. Remove from the heat and set aside.
Adding this mixture later in the roasting process gives you plenty of garlic flavor without exposing the minced garlic to the full cooking time.
Step 6: Add the garlic-herb butter
After the potatoes have roasted for 60 minutes total, remove the pan from the oven. If the reserved garlic-herb butter has firmed up, warm it over low heat for about 20 seconds, just until fluid.
Brush the garlic-herb butter over the potatoes, guiding some of the garlic and herbs between the slices rather than leaving everything on the exposed tips. Spoon any buttery pan juices over the tops. Roast for another 10 minutes.
Step 7: Finish with Parmesan and fresh parsley
Sprinkle the Parmesan over the potatoes, letting a little fall into the gaps. Return to the oven for 5 minutes, until the cheese is melted and lightly golden.
The potatoes are ready when the edges are crisp and a thin knife slides easily into the thickest part of the center. The planned roasting time is 75 minutes; unusually thick potatoes may need an additional 5–15 minutes. If the tops are already deeply browned, loosely shield them with foil while the centers finish cooking.
Transfer to a serving platter, spoon over any remaining buttery pan juices, and sprinkle with the parsley. Serve immediately while the edges are at their crispiest.
Pro Tips
- Keep the slices thin and even: Aim for 1/8 inch (3 mm). Thick slices take longer to cook and produce fewer crisp edges.
- Dry thoroughly after rinsing: Water trapped between the slices encourages steaming rather than browning.
- Let the oven open the potatoes: The cuts naturally spread as they roast. Do not force raw slices apart, which can snap the base.
- Grate the Parmesan finely: Freshly grated cheese settles into the cuts and melts more evenly than coarse shreds.
- Use tenderness as the final test: Potato shape affects timing. Test the center, not just a thin outer slice, before serving.
Variations
- Lemon and garlic: Add 1 teaspoon finely grated lemon zest to the garlic-herb butter after removing it from the heat. Finish with the parsley as directed.
- A little heat: Add 1/4 teaspoon crushed red pepper flakes to the garlic-herb butter along with the herbs.
- Vegetarian-friendly: Use 40 g of a Parmesan-style hard cheese made with vegetarian rennet; traditional Parmesan is typically made with animal rennet.
Storage & Make-Ahead
Refrigerate: Store leftovers in an airtight container in the refrigerator for up to 4 days. Refrigerate within 2 hours of cooking.
Reheat: Place chilled potatoes on a baking sheet and heat, uncovered, at 400°F (200°C) for 20–25 minutes, until hot throughout and the edges have crisped again. If needed, loosely cover with foil for the first 10 minutes to prevent excessive browning. Microwaving works for warming, but softens the crisp edges.
Prep ahead: Slice the raw potatoes up to 24 hours ahead, keep them completely submerged in cold water in a covered container, and refrigerate. Drain and dry very thoroughly before seasoning. For the best contrast between crisp edges and fluffy centers, roast just before serving.
Nutrition (per serving)
Estimated for 1 potato with one-quarter of the butter, oil, cheese, and seasonings. Actual values vary with potato size and ingredient brands.
Calories: 410 kcal | Carbs: 47g | Protein: 9g | Fat: 21g | Saturated Fat: 10g | Fiber: 4g | Sugar: 2g | Sodium: 620mg | Cholesterol: 38mg
