Potato Knish Recipe: Flaky Crust With Creamy Mashed Filling

Few dishes capture comfort food quite like potato knish—golden, flaky pastry encasing a creamy mashed potato filling that melts in your mouth. This recipe stays true to the traditional Jewish deli classic while offering foolproof techniques for achieving that perfect balance of textures at home.

The secret lies in the dough-to-filling ratio and proper sealing. A simple oil-based dough creates layers that bake up crisp and tender, while the potato mixture—enriched with caramelized onions and just enough butter—delivers that signature velvety interior. Whether served as an appetizer or main dish, these knishes bring deli-quality results to your kitchen.

Ingredients for Recipe for Potato Knish

Golden crust meets velvety filling—these deli-classic ingredients deliver that perfect knish texture at home.

The potatoes make this dish. Yukon Golds are ideal—they mash up buttery without turning gluey. For the onions, slow caramelization is key (that sugar helps), so don’t rush them. I grab my flour from King Arthur when I can, but any all-purpose works. The dough needs light-tasting oil—avocado or vegetable, nothing with strong flavor. And yes, you really need the full-fat sour cream in the filling (trust me on this).

No Yukon Golds? Russets work in a pinch, but add a splash of milk to the mash. Out of sour cream? Greek yogurt at equal measure keeps it creamy. The dough can handle half whole wheat flour if you want to healthify it. For the egg wash, milk or plant-based milk works if you’re out of eggs. And if you don’t have fresh chives, scallion greens or parsley brighten it up just fine.

Assembled knishes freeze beautifully for 3 months—bake from frozen, just add 10 minutes. The dough can rest overnight in the fridge (actually improves texture). Leftovers keep 4-5 days and reheat best in a toaster oven to crisp the crust. I always make a double batch—these disappear fast!

Step-by-Step Instructions for Potato Knish

Here’s how to nail that perfect balance of crispy crust and velvety potato filling every time.

Step 1: Prepare the Potato Filling

Start by boiling the 2.5 lb Yukon Gold Potatoes (peeled and quartered) in salted water until fork-tender, about 15-20 minutes. You want them to slide off a fork easily but not turn to mush. While they cook, melt 2 tbsp Unsalted Butter in a skillet over medium heat and add the 2 whole Yellow Onions with 1 tsp Granulated Sugar.

Cook the onions for 20-25 minutes, stirring occasionally, until they’re deep golden brown and caramelized. The sugar helps speed up the process and adds sweetness to balance the filling. Drain the potatoes well, then mash them with the remaining 4 tbsp Unsalted Butter, 0.5 cup Sour Cream, 0.5 tsp Freshly Ground Black Pepper, and 1 tsp Kosher Salt. Fold in the caramelized onions and set aside to cool.

Step 2: Make the Dough

In a large bowl, whisk together the 3 cups All-Purpose Flour, 1 tsp Baking Powder, and remaining 0.5 tsp Kosher Salt. Create a well in the center and add the 0.33 cup Vegetable Oil and 2 whole Large Eggs. Use a fork to gradually incorporate the dry ingredients into the wet until a shaggy dough forms.

Turn the dough onto a lightly floured surface and knead gently for 3-4 minutes until smooth and elastic. The dough should be soft but not sticky—add a sprinkle of flour if needed. Wrap it in plastic and let it rest at room temperature for 30 minutes. This relaxation period makes the dough easier to roll out and prevents it from shrinking when baked.

Step 3: Assemble the Knishes

Divide the rested dough into 6 equal portions and roll each into a thin oval about ⅛-inch thick. Place about ½ cup of the cooled potato filling in the center of each oval. The filling should be thick but not overflowing—you want a good ratio of crust to filling in every bite.

Fold the dough over the filling, pinching the edges tightly to seal. I like to use a fork to crimp the edges for a decorative touch and extra security. Place the knishes seam-side down on a parchment-lined baking sheet. Brush the tops with a beaten egg (use one of the Large Eggs if you have extra) for that golden, glossy finish.

Step 4: Bake to Golden Perfection

Preheat your oven to 375°F and position a rack in the middle. Bake the knishes for 25-30 minutes, rotating the pan halfway through, until they’re deep golden brown and the crust is crisp. You’ll know they’re done when the internal temperature reaches 190°F—this ensures the filling is heated through and the crust is fully cooked.

Let them cool on the baking sheet for 10 minutes before serving. This brief rest allows the filling to set slightly so it doesn’t spill out when you cut into them. Garnish with the 2 tbsp Fresh Chives just before serving for a pop of color and freshness. The contrast between the flaky, buttery crust and creamy potato filling is what makes these knishes irresistible.

Wine and Beer Pairings for This Dish

Crisp White Wines

I love pairing these knishes with a chilled Sauvignon Blanc—the bright acidity cuts through the richness of the butter and sour cream. A New Zealand style with its grapefruit notes works particularly well. For something more local, try a Long Island Sauvignon Blanc if you’re in the Northeast. 🍷

Light Lager Beers

When it comes to beer, you can’t go wrong with a classic pilsner. The crisp, clean finish of a German-style pilsner like Stiegl or Warsteiner complements the flaky crust without overpowering the delicate potato filling. The subtle bitterness also helps balance the richness.

Dry Sparkling Wines

For special occasions, I reach for a Brut Champagne or Prosecco. The effervescence cleanses your palate between bites, making each mouthful taste as fresh as the first. A Gruet Brut from New Mexico offers excellent quality at a reasonable price point.

Amber Ales

If you prefer something with more body, an amber ale works beautifully. The caramel malt notes in beers like New Belgium Fat Tire or Alaskan Amber mirror the caramelized onions in the filling. The moderate hop bitterness prevents the pairing from becoming too sweet.

Rosé Pairings

A dry Provence-style rosé brings out the best in these knishes. Look for pale pink options with crisp acidity and red fruit notes—Whispering Angel is a reliable choice. The wine’s refreshing quality contrasts nicely with the warm, comforting flavors of the dish. 💛

Non-Alcoholic Options

For those skipping alcohol, a sparkling apple cider offers similar palate-cleansing benefits. I particularly like Martinelli’s Gold Medal—its natural sweetness and bubbles complement the savory filling. A cold ginger beer also works well, with its spicy kick cutting through the richness.

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