Golden-brown skin-on potato pieces, with crispy and craggily edges.

Crispy Potatoes


This recipe is food chemistry in action: the potatoes are cooked in an alkaline solution, which accelerates the breakdown of pectin, significantly increasing the surface area of the starch granule and making them much softer than they would be cooked in only water (acidic water causes potatoes to be firmer and less likely to fall apart). When set in a hot oven the soft fluffy encasement of starch becomes crisper faster, much like a battered and fried coating.



  1. Cut the potatoes into chunky, 1 to 1 ½ inch cubes.
  2. Adjust an oven rack to center position and preheat the oven to 450°F.
  3. Bring 2 quarts (~2L) of water to boiling in a large pot.
  4. Add 2 Tbsp salt, the baking soda, and the potatoes. Stir to incorporate the baking soda.
  5. Simmer for ~10 minutes, until a knife meets little resistance when inserted into a potato chunk.
  6. When the potatoes are cooked, drain them and let them rest in the pot for ~30 seconds to allow excess moisture to evaporate.
  7. Pour the oil into the pot and toss to coat, shaking bowl roughly, until a thick layer of mashed potato–like paste has built up on the potato chunks.
  8. Season to taste if a little more salt and pepper is needed.
  9. Transfer the potatoes to a large rimmed baking sheet, spreading them out evenly (don’t use a nonstick pan because you will need to use a metal spatula later). Transfer to oven and roast, without moving, for 20 minutes.
  10. Use a thin, flexible metal spatula to release any stuck potatoes, and shake the pan and turn the potatoes.
  11. Continue roasting from another 20 to 30 minutes, until the potatoes are deep brown and crisp all over (aim for an internal temperature between 205°F and 212°F).
  12. Transfer the potatoes to a large bowl and add rosemary.
  13. Toss to coat and season with more salt and pepper to taste. Serve immediately.


Because they get battered and beaten during this recipe, the potatoes should be cut into very large chunks; they will lose some of this volume in the scrimmage and will end up a more reasonable size to eat. If they are cut too small initially they will end up as a sludge of very crispy mashed potatoes.

This recipe is based on the excellent recipe by J. Kenji López-Alt on Serious Eats.