The Food Lab: Better Home Cooking Through Science

work? How about this idea: you go do it yourself, then
make yourself comfortable on the couch” look before
rolling back over and nodding off. Sometimes I just don’t
understand her.
Nevertheless, I went into the kitchen and got to work on
the first batch of what would end up being my favorite
potato recipe in years.
Here’s the idea: We all love potato gratin, correct? The
creamy, layered casserole of potatoes and cream with a crisp
browned top. We also love Hasselback potatoes, those cute
side dishes achieved by making thin, parallel slices almost
all the way through a potato, stuffing butter and cheese in
between them, and roasting them until golden brown and
crisp. What if I were to combine the two concepts into one
gloriously crispy, creamy, crunchy, cheesy casserole?
The dish starts out just like most potato gratins: sliced
potatoes. If you’ve got an inexpensive Japanese mandoline
slicer, then it’s a snap. I tried it with both peeled and
unpeeled potatoes and preferred the cleaner crunch you get
from peeled potatoes. From there, it progresses like a
standard gratin: I mix heavy cream, grated cheese (I use
Comté and Parmesan), fresh thyme leaves, salt, and pepper
in a bowl, then I add the potatoes and toss them all together.
This step is worth taking your time with: it’s crucial that
every single potato slice gets coated on all sides with the
mixture. That means prying or sliding apart all the slices of
potato that are stuck together and dipping them into the fatty
mixture.
Here’s where we turn things on their head: rather than
stacking sliced potatoes horizontally like in a traditional