Crispy-Edged Pommes Boulangère with Thyme and Onions

Why You’ll Love This Recipe

• Classic French comfort: tender, savory layers with irresistibly crisp edges.
• Simple pantry ingredients elevated by careful layering and thyme-scented stock.
• Hands-off baking makes it weeknight-friendly, yet elegant enough for guests.
• Flexible: easily vegetarian, rich with duck fat, or even lightly cheesy if you like.

Grocery List

• Produce: Yukon Gold potatoes, yellow onions, garlic, fresh thyme, bay leaves (dried or fresh)
• Dairy: Unsalted butter
• Pantry: Extra-virgin olive oil, low-sodium chicken or vegetable stock, dry white wine (optional), kosher salt, black pepper, flaky sea salt

Full Ingredients

Main Dish

• 2.2 lb (1 kg) Yukon Gold potatoes, peeled and sliced 1/8 in (3 mm) thick
• 2 large yellow onions (about 1 lb/450 g), thinly sliced pole-to-pole
• 3 tbsp unsalted butter
• 2 tbsp extra-virgin olive oil
• 2 cups (480 ml) low-sodium chicken or vegetable stock, warmed
• 3 garlic cloves, minced
• 1 tbsp fresh thyme leaves (from 8–10 sprigs)
• 2 bay leaves
• 1 1/2 tsp kosher salt, divided
• 3/4 tsp freshly ground black pepper, divided
• Optional: 1/4 cup (60 ml) dry white wine for deglazing

Finishing

• 1 tbsp unsalted butter, melted (or 1–2 tbsp duck fat)
• Flaky sea salt, to taste
• Extra fresh thyme leaves, for garnish

Step-by-Step Instructions

Step 1: Heat the oven and prepare the dish

Preheat the oven to 375°F (190°C). Butter a 2-quart (2-liter) shallow gratin dish or a 12-inch (30 cm) oven-safe skillet. Warm the stock in a small saucepan over low heat; warm stock speeds up cooking and promotes creamy layers.

Step 2: Slice and season the potatoes

Peel potatoes and slice 1/8 inch (3 mm) thick using a mandoline or sharp knife. Briefly rinse the slices under cold water to remove surface starch, then pat completely dry with towels—dry slices help the top get crisp. Toss the potatoes with 1 teaspoon kosher salt and 1/2 teaspoon black pepper.

Step 3: Sweat the onions with thyme

In a large skillet over medium heat, melt 3 tablespoons butter with 2 tablespoons olive oil. Add onions and a pinch of salt; cook, stirring occasionally, until soft and lightly golden at the edges, 7–8 minutes. Stir in garlic and thyme; cook 1 minute until fragrant. Deglaze with white wine, if using, and reduce by half, about 1 minute. Stir in the warm stock, bring just to a simmer, then remove from heat.

Step 4: Layer the potatoes and onions

Arrange a tight shingled layer of potatoes in the prepared dish. Spoon over some onion mixture (without flooding the top), then continue layering potatoes and onions. Finish with a neat, overlapping top layer of potatoes. Tuck the bay leaves into the middle layers. Pour the hot stock mixture around the edges and corners so it seeps down while the top layer remains mostly above the liquid—this is key for crisp edges.

Step 5: Cover and bake until tender

Cover the dish first with a piece of parchment (prevents sticking), then with foil, sealing well. Bake for 40 minutes, until the potatoes are mostly tender and a knife meets slight resistance in the center.

Step 6: Uncover and crisp the top

Remove foil and parchment. Baste the top with a few spoonfuls of the pan juices, then brush with 1 tablespoon melted butter (or duck fat). Increase oven temperature to 425°F (220°C) and bake uncovered for 25–30 minutes, rotating once, until the top is deep golden, edges are lacy and crisp, and most of the liquid has been absorbed with small bubbles around the sides.

Step 7: Rest, finish, and serve

Let the dish rest for 10 minutes to set the layers. Discard bay leaves. Sprinkle with a pinch of flaky sea salt and extra thyme leaves. Serve straight from the dish, scooping to showcase the tender interior and crisp top.

Pro Tips

• Slice evenly at 1/8 inch (3 mm). Uniform slices cook at the same rate and make beautiful layers.
• Keep the top layer mostly above the liquid so it can brown and crisp instead of steaming.
• Use parchment under foil to prevent the top layer from sticking when you uncover.
• Warm stock speeds up cooking and keeps the texture creamy rather than waterlogged.
• Yukon Golds are ideal: they hold their shape yet turn tender and buttery.

Variations

• Duck Fat Finish: Swap the finishing butter for 1–2 tablespoons duck fat for a bistro-style richness and extra crisp edges.
• Vegan & Umami: Use olive oil only and vegetable stock; whisk 1 teaspoon white miso into the warm stock for deeper savoriness.
• Lightly Cheesy (not traditional): Sprinkle 1/2 cup (55 g) grated Gruyère over the top for the final 10 minutes.

Storage & Make-Ahead

Refrigerate leftovers in an airtight container for up to 4 days. Reheat covered at 350°F (175°C) for 15 minutes, then uncover 10 minutes to re-crisp. For make-ahead, you can par-bake covered for 35–40 minutes, cool, and refrigerate up to 2 days; finish at 425°F (220°C) for 25–30 minutes. Freezing is possible (up to 2 months, tightly wrapped) but texture is best fresh; thaw overnight and re-crisp at 425°F (220°C).

Nutrition (per serving)

Approximate: 270 calories; 12 g fat (6 g saturated); 35 g carbohydrates; 4 g fiber; 4 g protein; 480 mg sodium. Values will vary with stock and salt choices.