Best-Ever Potato Knishes

1 . Stage

Make dough: in a large bowl, whisk to combine flour, baking powder, and salt. In a medium bowl or measuring cup, combine vegetable oil or schmaltz with warm water, egg, and white vinegar.

2 . Stage

Make a well in the dry ingredients and pour liquid ingredients into the center. Stir to combine until a ball of dough forms. Transfer dough to a clean work surface and knead to ensure all flour is evenly incorporated, 1 to 2 minutes. 

3 . Stage

Return dough to bowl and cover with plastic wrap. Let rest for 30 minutes to 1 hour at room temperature. (Refrigerate dough if not using within the hour. Dough can be left in the fridge up to 3 days, bring up to room temperature before using.)

4 . Stage

Caramelize onions: In a large skillet over medium heat, combine butter or schmaltz and olive oil. When butter has melted, add onion and thyme if using. Season with salt and pepper and reduce heat to medium-low. Cook, stirring occasionally, until onions are caramelized and golden, 45 to 50 minutes. 

5 . Stage

Steam potatoes: Fill a large pot with 1" of water and place a steamer basket inside. Bring water to a boil, then add potatoes and cover with a lid. Cook until potatoes are tender, 15 to 20 minutes. (We like to insert a paring knife into the thickest part of a piece of potato. If the potato slides off when the knife is lifted, they're good to go!)

6 . Stage

Carefully remove steamer basket and drain water from pot. Transfer potatoes to pot, add sour cream and season with salt. Mash until mostly smooth (some lumps are OK!) and taste for seasoning. 

7 . Stage

When onions are done, remove thyme stems if used, then transfer onions to bowl with potatoes and stir to combine. Taste for seasoning and add more salt and/or pepper if needed.

8 . Stage

Assemble knish: line a large baking sheet with parchment paper and preheat oven to 375°. Split dough in half, placing one half back under plastic wrap. (It’s normal for some oil to sweat out of the dough while it’s resting. Knead it a couple times in the bowl to reincorporate oil if needed.)

9 . Stage

Using your hands, shape dough into a rectangle, then roll out into a large rectangle that is about 1/8” thick and between 12” and 15” on the long side. (This dough is very forgiving and doesn’t easily stick to surfaces, so don’t worry about being too rough with it!) Transfer half your potato mixture to the dough, and create a 2” wide log parallel to the 12”-15” edge of dough closest to you, 1”-2” from the bottom edge. Lift the 1”-2” of excess dough over the potato mixture, then carefully roll potato mixture away from you until you reach the other end of the dough, like rolling a cigarette. Arrange so the seam is on the bottom, and adjust roll if needed so that potato filling is evenly distributed.

10 . Stage

Trim ends of dough so it is even with the potato filling. Using the dull side of a dinner knife, make light indentations every 2”-2 ½” so that your cylinder is divided into 6 equally sized pieces. Use the sharp side of your dinner knife to cut through each knish.

11 . Stage

To shape your knishes: to make the bottom, use your finger to gently press the filling inward, then stretch the dough over the filling and pinch to seal. Flip the knish over so that the bottom is touching a clean work surface. For the top, use your thumbs and pointer fingers to press the cut dough in towards the center, so there is a slight indent and some filling showing. Repeat with remaining knishes, then repeat entire process with second piece of dough.

12 . Stage

Place knishes on prepared baking sheet and brush with egg and water mixture. Bake, turning pan halfway through, until golden, 45 to 50 minutes. Let cool at least half an hour before serving.

13 . Stage

Steam potatoes: Fill a large pot with 1" of water and place a steamer basket inside. Bring water to a boil, then add potatoes and cover with a lid. Cook until potatoes are tender, 15 to 20 minutes. (We like to insert a paring knife into the thickest part of a piece of potato. If the potato slides off when the knife is lifted, they're good to go!)

14 . Stage

Carefully remove steamer basket and drain water from pot. Transfer potatoes to pot, add butter and season with salt. Mash until mostly smooth (some lumps are OK!) and taste for seasoning.

15 . Stage

Heat vegetable oil in a medium skillet over medium heat. Add coriander and cumin seeds and cook until fragrant, about 30 seconds to 1 minute. Next, add peas, chaat masala, and turmeric. Cook until fragrant, 30 seconds to 1 minute more, then add mixture to pot with mashed potatoes and stir to incorporate. Fold in cilantro.

16 . Stage

Assemble knish: line a large baking sheet with parchment paper and preheat oven to 375°. Split dough in half, placing one half back under plastic wrap. (It’s normal for some oil to sweat out of the dough while it’s resting. Knead it a couple times in the bowl to reincorporate oil if needed.)

17 . Stage

Using your hands, shape dough into a rectangle, then roll out into a large rectangle that is about 1/8” thick and between 12” and 15” on the long side. (This dough is very forgiving and doesn’t easily stick to surfaces, so don’t worry about being too rough with it!) Transfer half your potato mixture to the dough, and create a 2” wide log parallel to the 12”-15” edge of dough closest to you, 1”-2” from the bottom edge. Lift the 1”-2” of excess dough over the potato mixture, then carefully roll potato mixture away from you until you reach the other end of the dough, like rolling a cigarette. Arrange so the seam is on the bottom, and adjust roll if needed so that potato filling is evenly distributed.

18 . Stage

Trim ends of dough so it is even with the potato filling. Using the dull side of a dinner knife, make light indentations every 2”-2 ½” so that your cylinder is divided into 6 equally sized pieces. Use the sharp side of your dinner knife to cut through each knish.

19 . Stage

To shape your knishes: to make the bottom, use your finger to gently press the filling inward, then stretch the dough over the filling and pinch to seal. Flip the knish over so that the bottom is touching a clean work surface. For the top, use your thumbs and pointer fingers to press the cut dough in towards the center, so there is a slight indent and some filling showing. Repeat with remaining knishes, then repeat entire process with second piece of dough.

20 . Stage

Place knishes on prepared baking sheet and brush with egg and water mixture. Bake, turning pan halfway through, until golden, 45 to 50 minutes. Let cool at least half an hour before serving.

21 . Stage

Steam potatoes: Fill a large pot with 1" of water and place a steamer basket inside. Bring water to a boil, then add potatoes and cover with a lid. Cook until potatoes are tender, 15 to 20 minutes. (We like to insert a paring knife into the thickest part of a piece of potato. If the potato slides off when the knife is lifted, they're good to go!)

22 . Stage

Carefully remove steamer basket and drain water from pot. Transfer potatoes to pot, add sour cream and season with salt. Mash until mostly smooth (some lumps are OK!) and taste for seasoning.

23 . Stage

Using a clean kitchen towel, squeeze all excess moisture out of spinach, then transfer to pot with potatoes.

24 . Stage

In a large skillet over medium heat, heat oil. Add green onions and cook until softened and translucent, 2 to 4 minutes. Add garlic, oregano, red pepper flakes if using, and season with salt and pepper. Cook until fragrant, 1 minute more, then transfer mixture to bowl with potatoes.

25 . Stage

Add dill and lemon zest to bowl with potatoes and stir until all ingredients are evenly mixed. Gently fold in cubed feta and season to taste with salt and pepper if needed. Carefully pour sesame seeds onto a small shallow plate.

26 . Stage

Assemble knish: line a large baking sheet with parchment paper and preheat oven to 375°. Split dough in half, placing one half back under plastic wrap. (It’s normal for some oil to sweat out of the dough while it’s resting. Knead it a couple times in the bowl to reincorporate oil if needed.)

27 . Stage

Using your hands, shape dough into a rectangle, then roll out into a large rectangle that is about 1/8” thick and between 12” and 15” on the long side. (This dough is very forgiving and doesn’t easily stick to surfaces, so don’t worry about being too rough with it!) Transfer half your potato mixture to the dough, and create a 2” wide log parallel to the 12”-15” edge of dough closest to you, 1”-2” from the bottom edge. Lift the 1”-2” of excess dough over the potato mixture, then carefully roll potato mixture away from you until you reach the other end of the dough, like rolling a cigarette. Arrange so the seam is on the bottom, and adjust roll if needed so that potato filling is evenly distributed.

28 . Stage

Trim ends of dough so it is even with the potato filling. Using the dull side of a dinner knife, make light indentations every 2”-2 ½” so that your cylinder is divided into 6 equally sized pieces. Use the sharp side of your dinner knife to cut through each knish.

29 . Stage

To shape your knishes: to make the bottom, use your finger to gently press the filling inward, then stretch the dough over the filling and pinch to seal. Flip the knish over so that the bottom is touching a clean work surface. For the top, use your thumbs and pointer fingers to press the cut dough in towards the center, so there is a slight indent and some filling showing. Repeat with remaining knishes, then repeat entire process with second piece of dough.

30 . Stage

Dip the bottoms of each knish into sesame seeds, then place on prepared baking sheet. Brush the tops with egg and water mixture and sprinkle with remaining sesame seeds. Bake, turning pan halfway through, until golden, 45 to 50 minutes. Let cool at least half an hour before serving.