I have been trying to prepare rösti a number of times these last few weeks with meager results. I have tried both making fresh rösti from grated potatoes and using vacuumed ready-to-fry rösti from the supermarkert.
Grating potatoes myself took a lot of time and yielded the worst results, so I will describe my issue based on the slightly better experience I had with processed mixes (according to the package those only contain potatoes and vegetable oil).
- The rösti tends to stay too fluffy, and when pressed with a spatula (tried metal, plastic, and wood) constantly sticks to it – so that I cannot compact the mixture well.
- The lower layer of the rösti became somewhat robust a couple of times, but trying to lift it from the pan to turn it around always broke the rösti into bits.
- I can't seem to find an optimal ammount of pressing the rösti together: press too much and the rösti sticks to my spatula as well as to the bottom of the pan, press it too little and it doesn't clunk together well.
I am sure at least my "sticking" problems could be diminished by more advanced kitchen utensils (not that mine are bad, but they are definitely not chef-grade ^^), still, seeing as this is a traditional dish which peasants likely prepared in iron pans, I would expect it to be comparably easy to omelettes. What am I missing? And no, oiling the pan better doesn't help, the oil just gets absorbed by the rösti and makes them fattier.
Best Answer
Get rid of the water. That's probably why you have had better luck with the prepared rosti. After shredding, salt the potatoes and wring the heck out of them using a clean towel. America's Test Kitchen has a fun little trick in their recipe for latkes. They wring the salted and shredded potatoes over a measuring cup. After a few minutes, the starch from the potato settles in the bottom of the cup. Carefully pour off the water and add the starch back into the potato. As Bridget says, "You know the amount of starch is right, because it came out of the same potato."
Also, par-cook the potato after wringing, before frying. A microwave works well for this, you can also use an oven at a moderate (350F, 175C) temperature, covered with aluminum foil.
For French fries you want to remove the starch (that's why a water soak is recommended) but of course with French fries you're not trying to keep them stuck together. You want rosti to stick to itself, but not the pan. Keeping the starch but eliminating the water will help.