Potato Knish

also called knish · knishes · square knish · potato knish · baked knish · knysh

The table

2 lb(900 g, peeled, in chunks)russet potatoesboil the potatoes 20 minmash coarse, season hardroll thin, fill the sheet, lay the topbrush with egg, bake 45 min, cut into squares
3 qtwater
1 Tbskosher salt
2 large(diced)yellow onionsfry the onions 20 min in schmaltz
1/4 cup(60 mL)schmaltz
2 tspkosher salt
1 tspblack pepper
2 cups(250 g)all-purpose flourmix the dough, rest 1 hr
1 tspbaking powder
1/2 tspkosher salt
1 largeegg
1/4 cup(60 mL)neutral oil
1/2 cup(120 mL)warm water
1 tspwhite vinegar
1 large(beaten with a splash of water)egg
Tap anything to cross it off.

What to lay out

Everything the recipe asks for, sitting under the step that eats it. Tick each one as you measure it.16 things to get out.

Pans and tools

1boil the potatoes 20 min

2fry the onions 20 min in schmaltz

3mix the dough, rest 1 hr

4mash coarse, season hard

goes in with what steps 1 and 2 made

6brush with egg, bake 45 min, cut into squares

goes in with what step 5 made

Cooking it

Start to finish is the longest chain through the table, so branches that overlap are counted once. That is why the waits add up to more than the clock — and it only holds if you get them going together.

Tap a step when it is done; the next one lights up.

The clock

Start to finish
at least 1 hr 45 mintwo waits that overlap count once
Needs you
20 minof the steps that give a time

2 of the 6 steps never say how long they take, so both numbers are floors. The recipe itself says 2 hr 15 min.

  1. mix the dough, rest 1 hr

    1 hrwalk awayfrom the start

  2. boil the potatoes 20 min

    20 minwalk awayfrom the start

  3. fry the onions 20 min in schmaltz

    20 minneeds youfrom the start

  4. mash coarse, season hard

    not timed20 min in

  5. roll thin, fill the sheet, lay the top

    not timed1 hr in

  6. brush with egg, bake 45 min, cut into squares

    45 minwalk away1 hr in

Drawn to scale, so a long wait really does take up the room it takes. The shortest stretches keep a sliver so they stay visible; their times are printed beside them. Bars that line up are happening at the same time.

You'll need sheet pan

Goes with

See how it is written
>> title: Potato Knish
>> category: Dumplings & Rolls
>> tags: potato, onion, baked, pastry, deli
>> counters: Deli
>> aka: knish, knishes, square knish, potato knish, baked knish, knysh
>> pairs-with: schmaltz, sour-dill-pickles, chicken-broth
>> servings: 8
>> time: 2 hr 15 min
>> step.1: mix the dough, rest 1 hr
>> step.2: boil the potatoes 20 min
>> step.3: fry the onions 20 min in schmaltz
>> step.4: mash coarse, season hard
>> step.5: roll thin, fill the sheet, lay the top
>> step.6: brush with egg, bake 45 min, cut into squares

Mix @all-purpose flour{2%cups}(250 g), @baking powder{1%tsp} and @kosher salt{1/2%tsp} with @egg{1%large}, @neutral oil{1/4%cup}(60 mL), @warm water{1/2%cup}(120 mL) and @white vinegar{1%tsp} into a soft, slightly sticky dough, knead it for a minute, then oil it, cover it and ~rest{1%hr}. Oil, not butter or schmaltz: this dough has to stretch nearly transparent and fat in the sheet is what lets it, while the vinegar keeps it from springing back.

Boil @russet potatoes{2%lb}(900 g, peeled, in chunks) in @water{3%qt} with @kosher salt{1%Tbs} and ~boil{20%min}, until they fall off a knife, then drain them dry in the hot pan for a minute.

Fry @yellow onions{2%large}(diced) in @schmaltz{1/4%cup}(60 mL) over medium heat and ~fry{20%min}, until deep gold. Two onions to two pounds of potato looks like too much and is exactly right — a knish is an onion dish that happens to be held together by potato.

Mash @&(~2)drained potatoes{} coarse with @&(~1)fried onions{} and all the fat in their pan, @kosher salt{2%tsp} and @black pepper{1%tsp}. Leave it lumpy, and taste it: cold filling in a baked shell tastes blander than the spoonful you tried hot, so season it past where you think it should stop.

Roll @&(~4)rested dough{} out on a floured cloth into a large thin rectangle, stretching the last of it with the backs of your hands until you can nearly see through it, then line a #sheet pan{}, spread @&(~1)potato filling{} across the bottom in an even inch-thick layer, and fold the overhanging dough over the top to seal it. This is the square knish, the one baked in a sheet and cut. The round one is a different food under the same word: rolled into a rope, pinched into pucks and fried.

Brush @&(~1)filled sheet{} with @egg{1%large}(beaten with a splash of water) and ~bake{45%min} at 400°F (200°C), until the top is glossy and deep brown, then cut it into eight squares while it is still warm. Eaten hot with a stripe of yellow mustard, standing at the counter, out of a paper bag.