Vegan: Crispy Potato, Onion, and Mushroom Rösti
Note: For the four weeks between January 14th and February 11th, I'm adopting a completely vegan lifestyle. Every weekday I'll be updating my progress with a diary entry and a recipe. For past posts, check here!
Last Saturday, we had a surprise guest over for a late morning brunch. Actually, is surprise the best way to describe a friend of your wife's who's been staying on your couch for the last couple nights? What I meant was that the guest wasn't a surprise, and the brunch wasn't a surprise. What was a surprise was that when I got into the kitchen that morning, I realized that my repertoire of vegan-friendly lunch dishes was sorely lacking.
Thing is, normally I'm great at improvising a brunch. A flavorful vegetable hash cooked in duck fat with some shredded leftover meat, poached eggs, good hollandaise sauce, a cheese plate, perhaps a few homemade sausages—these are the things I'm used to whipping out when we've got a guest over on a weekend. But cooking brunch as a vegan was a new one for me.
With no eggs or cheese to fall back on, and once again not enough planning I briefly pondered serving her a tofu scramble then realized that it'd probably only enforce whatever stereotypes she already has of vegans and opted instead to improvise with the vegetables I had on-hand. Salad greens and dark leafy greens have their place in my fridge and my plate, but a guest spot at the brunch table is not one of them—at least not unless they're gonna come with a runny egg and lardons. I wanted a brunch that was as carb-heavy hearty, greasy, and satisfying as the best omnivore brunches around (even vegans can choose to be unhealthy once in a while).
A Tex-Mex or Mexican-themed brunch was a distinct possibility, given that I had leftover Vegetarian Bean Chili and a stack of tortilas, not to mention a great recipe for Vegan Chilaquiles with Pepitas, but I know my wife has been eating that chili for lunch for days now. I would not be so cruel as to inflict it upon her for brunch as well.
Scanning my fridge and noticing the squeeze bottle of Vegan Mayonnaise, I realized that was my in. As a vegan, there is a distinct lack of rich, creamy-textured foods, and for brunch, that texture is almost essential. It may seem weird to build a brunch around a sauce, but that's how my brain works. From there, it was a quick jump to crispy potatoes, and from there, another simple leap to a stuffed rösti once I found the mushrooms and thyme in the bottom of my fridge.
Crispy and golden brown on the outside, creamy and tender in the middle with some good garlicky mayo (aïoli, if you will) for dipping in, the key to a really great rösti is twofold: first, the shape of the potatoes. You can grate them on a box grater or in the food processor, but when you do, you end up rupturing potato cells, releasing a ton of liquid and starch from inside them. You're forced to squeeze the shreds dry and your rösti comes out starchy and sticky, even with relatively low-starch potatoes like Yukon Golds.
Much better (though slightly more difficult) is to cut them on a mandoline slicer (check out this article for my recommendation). If you have a fancy one with extra teeth, it'll cut the potatoes directly into 1/16th-inch shreds for you. If you don't, it's easy enough to slice the potatoes into thin planks then use a knife to get the matchsticks you need. A sharp mandoline and a sharp knife = less ruptured cells = less sticky starch release = better texture and more potato flavor in each bite.
The other key to a great rösti is to parcook the potatoes before frying them. Anybody who's worked the french fry station at a restaurant knows that potatoes will begin to oxidize as soon as you cut them. Over the course of 15 minutes or so, a cut potato will go from being pale white to reddish brown and eventually to black. You don't want your potatoes to be black.
Storing sliced potatoes in water will prevent this from happening (or at least slow it down), but it also rinses away lots of starch. Too little starch is just as bad as too much starch in a rösti, so I avoid rinsing or submerging my taters in water at any point. Par-cooking the potatoes accomplishes the goal of preventing them from browning, and also leads to a better texture in the finished product—you don't have to worry about raw potato in the center of the pie.
This is one case where the microwave is actually the best tool for the job. It allows you to rapidly cook the potatoes without either adding moisture, or losing an excessive amount.
For this semi fancy-pants version, I sautéed onions and mushrooms until a deep golden brown and flavored them with a bit of thyme to form a central layer in my potato cake. You could use whatever sautéed vegetables you want (or even cheese, if you are so inclined).
After you've got your stuffing, cooking the rösti is a simple matter of moderate heat. I use a well-seasoned cast iron pan for even, steady heat, but you can use a good non-stick pan if you don't have a cast iron. Crisping the potatoes properly takes a bit of time, which gives you plenty of time to brew your coffee or squeeze your mangoes, or whatever it is you serve with brunch.
This dish will be making return appearances on my table.
Get The Recipe
About the author: J. Kenji Lopez-Alt is the Managing Editor of Serious Eats where he likes to explore the science of home cooking in his weekly column The Food Lab. You can follow him at @thefoodlab on Twitter, or at The Food Lab on Facebook.