Fjällfil Potato Knishes

I know. It’s weird to put fjällfil in knishes. Hear me out, though. The best mashed potatoes are made with the most disgusting yogurts… I know some of you grew up w/ this yogurt and like it, but it’s less yummy to most of us who didn’t. If you aren’t breaking your viili in order to beat the fjällfil (do not recommend!), there’s nothing we have that does as bang-up of a job with the taters as fjällfil. Nothing at all; I’ve worked hard to find another. Similarly, potato knish is the best kind of knish (fight me!), so it stands to reason that if you have fjällfil (or any other yogurt, really), you may as well mash (haha) the two culture’s products and get the best of all worlds! It’s all about getting the best outta them taters!

This is the only reason I keep this yogurt around, since Child Tester isn’t having any of it due to its extreme funk, and I only get it out of the freezer to reculture if mashed potatoes are involved. I’m a mashed potatoes pusher anyway, so this probably isn’t a huge surprise.

Knishes, for those of you not familiar, are kind of like pasties, empanadas, runzas (I’m sorry, Nebraska. I still don’t care for these), and so forth: they’re some sort of filling encased in a crust of some kind. They normally include a fatty dough that can be made thin like pie crust, but not always. You can use pie crust or puff pastry if you want. You can also use potato flakes if you want. I definitely used potato flakes for mine. I also prefer using potato flakes for gnocchi and breads over fresh potatoes. For those of you who don’t know what potato flakes are, these are also called instant potatoes. They’re made by making massive batches of mashed potatoes (sometimes with stuff in them, but most are just plain, peeled potatoes), drying them, and scraping them off the dryer for packaging. These are great to use in situations where you don’t really need fresh ones. Ross makes Child Tester aligot with them, though he and CT call them “Abba potatoes.”

I’m using homemade pie crust today, because I sprained both of my knees last Monday (yeah, I’m that kind of talented. Also, it turns out that middle aged is not just a number and that no one was lying to me that I’d get old enough that the injuries really do heal differently) so I’m not doing any baking that can’t mostly be performed while sitting in a chair. The knees are healing well, but they’re still not ready for standing to make dough or sitting on the floor like I normally do. Thus, I had CT make the pie crust, since hers is better than mine anyway and she loves baking. If you really want to make these more traditionally (which eradicates the fjällfil and either uses no extra dairy or uses plain milk), the link above will show you a couple of traditional methods. I think you probably could make this work with biscuit dough, but someone will need to tell me if that’s good or if they’re mad at me for saying they should experiment.

You should also know that I only used enough dough (half) for about 6 knishes, because I saved the second half of my pie crust for the pumpkin pie CT said she wants over Thanksgiving. Also, I prefer both to overfill them and to eat pinches of mashed potatoes with her while we’re filling them, so I make the same amount of filling and use it with half of the right amount of dough. I’ll explain it properly below.

For those of you who’re really not sure about what to serve as condiments, it’s up to you. I personally eat them plain, but some people like a squirt of brown mustard (it really needs to be deli mustard, not ballpark yellow) or a bit of sour cream. These are not eaten cold and should at least be warmed (in the oven or in a pan, not microwaved) before eating. Some people prefer them piping hot. You can make a lot of these ahead of time and freeze, too. Just toss them in the oven to reheat when you pull out as many as you need from the freezer!

I served these with fried beet and fennel bulb, which I made by glurping some olive oil in the pan, adding a massive beet that I’d peeled and cubed, some thyme, salt, what CT said was too much black pepper (not for us, it wasn’t, so she ate an extra knish and I got her beets!), and letting that sit in a medium heat pan until the beets were fairly soft. Then I added a fennel bulb that had been split in half lengthwise and thinly sliced. That all cooked together until the beets were barely burned. Very simple, but also satisfying.

Here’s what you’ll need

1/2 onion, finely diced

butter or oil (I used butter)

salt and pepper

1 pound of potatoes or 1 1/3 cups potato flakes and equal amount of water

salt and pepper

cheese if you want some in there (I considered it, but opted against it)

quarter cup of fjällfil or other funky yogurt (mine was a quarter cup on the nose since I wanted my filling just a hair drier than normal, but usually I would put a bit more, maybe 6 tablespoons instead of the 4 I used)

1-2 sheets of puff pastry, pie crust, or whatever kind of dough you decided to make: if you want them overfilled so they crack open while baking, use 1 sheet. If you want them the normal way, use 2.

1 egg + 1 tablespoon of water for egg wash

Here’s what you’ll do

Melt the butter in the pan, then add the onions and seasoning. This should all be done over low heat, though you’re welcome to cook your onions faster. Either way, they’re done when you they smell like hash browns. Put them in a bowl.

Cook, then peel, then mash your potatoes (or mix together your water and flakes; I do this with cold water). Add salt and pepper, cheese if using, and your yogurt or other dairy. Mix together well. It should be kind of moldable, but not stiff.

Heat your oven to 425F/220C/GM7. While that’s heating, make (if applicable) your dough and roll it out into a rectangle around 12x12 per half of the dough. You’ll do 2 of these if you’re doing it the normal way. Cut your dough into 6 equal/equalish pieces. Put either 1/3 cup (minus whatever you ate of each of those) in the middle of each, or 1/6 of a cup (ditto) in the middle of each.

Kind of like this, though you’ll roll your dough out better, I’m sure.

Bring all of the corners up to the top and tuck the edges around where the mashed potatoes are so the folds are overlapping enough to not leave any holes. If you have enough dough up top to do it, you can twist it gently and push it down a little bit to make a cute little spiral on top. If you don’t, fold it up however gets it sealed. If you’re overfilling, you need to know this isn’t going to work out for you with them looking super pretty.

Whisk up your egg with a bit of water and brush it onto your knishes.

Once you’ve got them put together, it’s bake time! Toss them in there for 15 (puff pastry) to 25 (biscuits) minutes. Mine took around 20.

Now it’s nom time!

Like I said, not pretty when overfilled, but your mouth won’t mind.