This Wild Mushroom-Potato-Onion Tart Is an All-Day Treat

From breakfast to dinner, this wild mushroom-potato-onion tart recipe by Melina Hammer satisfies every craving.

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It’s the season for comfort foods—which makes it the perfect time to page through Melina Hammer’s cookbook, A Year at Catbird Cottage. The Accord-based photographer and self-taught cook makes the most of local ingredients. The following recipe for wild mushroom-potato-onion tart would be delicious additions to your holiday table.

Tucked away at the base of the Shawangunk Mountains is a charming, one-bedroom bed & breakfast that Melina Hammer runs out of her home in Accord. Known as the Catbird Cottage, Hammer and her husband welcome guests to their cozy retreat in the Catskills and feed them hearty, seasonal meals. A food photographer by trade, Hammer “made a deep dive into cooking through the relationship I had with The New York Times, cooking, styling, and shooting food for features.” She does it all at Catbird—from foraging and fermenting to searing and roasting. “I also make a mean cocktail,” adds Hammer. She spent two years writing, cooking, and of course, photographing her debut cookbook, A Year at Catbird Cottage: Recipes for a Nourished Life, which serves up over 100 recipes that highlight the bounty of the Hudson Valley, as well as foraging guides and sustainable practices. “I wanted to create a native plant and kitchen garden, forage food right outside my door, and live each day witnessing the many creatures great and small,” explains Hammer. “My cookbook is an adventure and a love story which unfolds, season to season.”

While this wild mushroom-potato-onion tart is a treat on its own, it’s also an ideal accompaniment for a larger breakfast, lunch, or dinner spread. Pair it with these poached eggs for a savory start to the day or, if you’re serving it for lunch or dinner, try this grain salad or this roasted chicken to round out the meal.

Wild Mushroom-Potato-Onion Tart

Course: Breakfast, Lunch, DinnerCuisine: American


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This versatile dish makes good use of meaty mushrooms. Sautéing the onions and mushrooms intensifies their character. This tart can serve as breakfast, lunch, or dinner.


  • 1 package prepared puff pastry, such as Dufour, thawed in the refrigerator

  • All-purpose flour, for dusting

  • 12 oz. any fresh wild mushrooms, or a mix of hen of the woods, oyster mushrooms, king boletes, or chanterelles

  • Extra-virgin olive oil

  • Kosher salt

  • Full-fat buttermilk (to paint the crust)

  • 3 oz. Gruyère, grated

  • 4 medium Yukon gold potatoes, sliced ¹/₈-in thick on a mandolin

  • ½ to 1 cup caramelized onions

  • Leaves from 5–9 sprigs fresh thyme

  • Freshly ground black pepper and flake salt

  • 3 stems fresh tarragon


  • Unfold the pastry onto a lightly floured sheet of parchment and roll to a rectangle. With a sharp paring knife, hold the edge perpendicular to the pastry and score a border 1 inch in from the edge, all the way around (Scoring a border helps puff up the crust as the butter within the laminated pastry melts, expanding the layers in the roaring hot oven. Transfer to a sheet pan and chill in the refrigerator.
  • Preheat the oven to 400°F.
  • Slice the mushrooms into ¼-inch pieces. In a large cast-iron skillet, cook the mushrooms with a drizzle of oil and a pinch of salt until they begin to collapse and brown, 5–7 minutes, turning occasionally. Remove the pan from the heat and set aside.
  • Bring the pastry out from the fridge. Paint the buttermilk onto the border. Sprinkle the Gruyère in an even layer onto the pastry, inside the border. Arrange the potato slices like shingles, followed by the caramelized onions, scattered around. Sprinkle half the thyme leaves, then add the mushrooms, followed by the remaining thyme leaves. Season with pepper and drizzle a very small amount of oil, just enough to kiss the surface in places.
  • Bake the tart on the sheet pan for 30 minutes or until the pastry is golden and the cheese is melted, rotating the pan after 20 minutes for even baking. Set the tart on a wire rack and cool for 5 minutes.
  • Cut into slices, season with flake salt and freshly ground pepper to taste, and sprinkle with fresh tarragon leaves plucked from their stems for garnish. Store any leftovers between layers of parchment, sealed in a container in the refrigerator, for up to 3 days. Reheat slices in a moderate oven or toaster oven for best results.
Photo by Melina Hammer

Related: These Hudson Valley Restaurants Serve up Scrumptious Fall Flavors

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