Today’s post is for all my fellow carb lovers out there.
What do you get when you wrap mashed potato and caramelized onions inside a pastry dough crust? HEAVEN. Also known as the Potato and Onion Knish.
Why are Potato and Onion Knish the book-inspired recipe for The Matchmaker’s Gift?
Main character Sara in The Matchmaker’s Gift makes a match between two rival NYC knish delis. I loved this detail in the novel, and given my love for a good knish, I thought that Potato and Onion Knish would be a perfect book-inspired recipe for this story.
It surprises me that a lot of people don’t know what a knish is. I grew up in Northern NJ, an area with a large Jewish population.
Many a lunchtime was spent at my local Jewish deli (which sadly went out of business years ago.) It was there that I had my first knish and fell in love with this deli staple.
What’s a knish?
The simplest and most basic way to describe a knish is a lump of mashed potato wrapped in pastry dough, then baked until golden brown and delicious. There are tons of variations on the knish out there, but I believe the classic filling is potato and onion.
If you’re a fan of pierogi *raises hand* you’re going to love knish. Or, do you enjoy a good Cornish pasty, pot pie, or Hot Pocket? You’re going to love knish.
And, obviously, if you love mashed potatoes — say it with me now — you’re going to love knish.
Is a knish without schmaltz still a knish? I think so.
Traditional knish recipes call for “schmaltz,” which is chicken fat. We all know that the Tart isn’t a health food blog, but even I draw the line at incorporating pure fat or grease into a dish.
However, that schmaltz is what gives a knish its robust flavor.
My Potato and Onion Knish uses chicken broth in both the mashed potatoes and the pastry crust to evoke that classic taste imparted by the schmaltz.
The pastry crust I used to make the knish is so buttery and tender that you really don’t miss the grease that the schmaltz would have provided, and you still get that savory hint of poultry in your dish.
What I love about Potato and Onion Knish
Um, what’s not to love about knish? There’s potato and pastry. BOOM. Done.
The pastry encasing the filling is all the good adjectives. Flaky. Crispy. Buttery. Tender. I think I’ve sold it right there, honestly.
But, if you need more: the mashed potato filling is creamy and dreamy, with a bit of a kick from the black pepper.
And, those caramelized onions. They’re my favorite part – so sweet and so savory at the same time. They make each bite of the knish perfect.
Although I don’t think it’s traditional, I folded caraway seeds into my potato and onion filling. I also sprinkled a few seeds on the tops of the knish before I baked them.
I always associate caraway seeds with good rye bread, and I associate good rye bread with a good Jewish deli. So, tossing some caraway into my Potato and Onion knish was a no brainer.
Is making knish difficult?
I’ll admit that I was a little intimidated to make knish. You know what, though? I worried for nothing.
Making Potato and Onion Knish was surprisingly easy.
The main components are mashed potatoes – something I could make with my eyes closed – and caramelized onions, which I’ve made before for my onion jam.
Caramelized onions take about an hour to cook. While you’re babysitting the onions, you can make the mashed potatoes and the pastry dough in the same time frame. Then you’ll be all set to roll out the dough, fill and shape your knish, and bake them off.
In the end, the “hardest” part was shaping the knish into that rustic round shape. But, but I found a little cheat that made things super easy.
How to Make and Shape a Knish
I like a generous amount of potato and onion filling in my knish. It’s the only way to go, really.
But an overstuffed knish means it’s a little hard to close all that yummy filling up inside the dough.
Thankfully, you’ll have some leftover dough after your trim the scraps to create a rectangle (see recipe instructions below).
I used these scraps to patch up the knish and encase the filling.
Don’t worry if the filling is pushing out of the top.
I was nervous about that, but there was no volcano action happening in the oven. The filling stays inside the knish while it bakes.
But, I do recommend patching the bottom opening of the knish with scrap pastry dough.
You don’t want the filling oozing out the bottom (gravity, you make things complicated) while the knish bakes, or when you take a big, honkin’ bite after it cools down a bit.
What do you serve with Potato and Onion Knish?
Potato and Onion Knish can be eaten on its own as a snack (a little nosh!), or you can have it as a hearty, comforting lunch with salad or soup. Try pairing it with White Cheddar and Cauliflower Soup or Apple Butternut Squash Soup.
Great salads to eat alongside the knish are a refreshing Mixed Berry Spinach Salad with Blackberry Vinaigrette or Watermelon and Arugula Salad, or with a protein-packed Chicken Caesar Pasta Salad.
If you’re looking for something heartier, the knish would also pair well with Shrimp and Kale Turmeric Curry or Chickpea Curry.
Top off your nosh with an Iced Dirty Chai Latte or a slice of Rose Honey Cake.
Potato and Onion Knish
Ingredients
MASHED POTATOES INGREDIENTS
CARAMELIZED ONIONS INGREDIENTS
- 2 large onions, peeled and very thinly sliced
- 3 tbsp extra-virgin olive oil
- 1/4 tsp salt, or to taste
- 1/4 tsp ground black pepper, or to taste
KNISH PASTRY DOUGH INGREDIENTS
- 2 cups all-purpose flour
- 1/2 tsp baking powder
- 1 tsp kosher salt
- 1 cup unsalted butter
- 2-4 tbsp low sodium chicken broth, COLD
- 1 egg beaten with some water (for washing)
Instructions
CARAMELIZED ONIONS COOKING INSTRUCTIONS
- Start making the caramelized onions first, since they will take the longest.
- Peel and thinly slice onions.
- Add the olive oil to a large skillet set over medium heat. Once oil is hot, carefully add all the onions to the skillet and stir to coat with the olive oil.
- Cook onions over medium heat for 45-60 minutes, or until soft and golden brown, stirring regularly every 5 minutes to ensure no onions start burning.
- Remove caramelized onions from heat and season with salt and pepper to taste. Set aside.
KNISH PASTRY DOUGH INSTRUCTIONS
- While the onions caramelize, make the pastry dough.
- Slice butter into thin pats. Set aside.
- Cut a piece of plastic wrap and place it aside.
- Whisk together the flour, baking powder, and salt in a medium bowl.
- Add the sliced butter to the bowl, then massage the butter into the flour, breaking up the pats with your fingers into smaller pieces. However, leave some larger pieces of butter in the mixture, as they will create tenderness later. After 3-4 minutes, you should have a crumbly dough mixture.
- Add the chicken broth to the flour mixture, one tablespoon at a time. Work the broth into the flour mixture by tossing it with your fingers to make sure all ingredients are moistened.
- You don’t want the dough to become entirely homogenous. You should be able to take a handful of dough crumbles into your hand, squeeze, and have the dough stay together – this means the dough is moist enough and you can stop adding broth.
- Put the remaining chicken broth back in the fridge to stay cold—you may need it later when you roll out the dough.
- Scoop the dough onto the plastic wrap and squeeze it together into a flat disc. Wrap the disc in the plastic wrap and refrigerate for 30-60 minutes.
MASHED POTATOES COOKING INSTRUCTIONS
- After putting your pastry dough in the fridge, and while the onions are still caramelizing, make the mashed potatoes.
- Peel and cut your potatoes, then place them in a medium pot.
- Fill the pot with chicken broth, enough so that the potatoes are completely covered by at least an inch of broth.
- Boil the potatoes over medium-high heat until fork tender.
- Drain the cooked potatoes, then add them back to the pot or place in a large bowl for mashing.
- Add the butter, milk, salt, pepper, and caraway seeds (if using) to the potatoes, then mash all together to your desired consistency. (I like my potatoes thick and smooth.)
- Set mashed potatoes aside and let cool.
KNISH FILLING INSTRUCTIONS
- Preheat the oven to 375F.
- Line a baking sheet with parchment paper and set aside.
- Stir the caramelized onions into the mashed potatoes until completely combined. Set aside. If the filling is still hot, let cool to room temperature.
- Roll out the pastry dough on a well-floured surface until the dough is roughly 11x15 in size and about 1/8 inch thick. If the dough keeps crumbling, work a little more of the reserved cold chicken broth into the dough and re-roll.
- Use a sharp knife to cut away the rough edges of the dough to create a perfect rectangle. Set the dough scraps aside to use later.
- Scoop the room temperature mashed potato and onion filling in a row across the length of the dough, leaving about1 inch from the pastry’s edge. (See photo above.)
- Fold the top flap of dough over the filling so you have a little log. (See photo above.)
- Roll up the remaining dough over the filling, then place the log seam-side-down on your work surface. (See photo above.)
KNISH SHAPING INSTRUCTIONS
- Trim the ends off the log; discard the potato-filled dough scraps.
- Divide the log into 8 equal(ish) pieces using a sharp knife. (See photo above.)
- Take one piece and place it in the palm of your hand so that the open sides are now the top and bottom of your knish. Gently pull the edges of the openings and gather them together to seal off the opening. Some filling might squish out, and that’s okay.
- If there isn’t enough dough to cover both openings, take a reserved scrap of dough and fold it around the BOTTOM of the knish. You want the bottom to be sealed, but the top of the knish can remain a bit “open” with some filling peeking out.
- Repeat the shaping process with the remaining seven pieces until you have eight round knish.
KNISH BAKINGINSTRUCTIONS
- Whisk together the egg and a few drops of water in a small bowl to create an egg wash.
- Place the round knish on the baking sheet a few inches apart; they will poof up in the oven.
- Brush each knish with the egg wash. Sprinkle tops of knish with caraway seeds, if desired.
- Bake the potato and onion knish at 375F for 20-30 minutes, or until the knish are golden brown.
- Remove knish from the oven and let cool on baking sheets or wire rack. Serve warm.
