a bit of buttermilk, which is just thick enough to coat them
in a layer of liquid that then forms a thin sheath when
combined with the flour and cornstarch I dredge them in.
Of the dozen kinds of flour I tried, flour, cornstarch, and
potato starch were the favorites. Flour on its own, with its
relatively high protein content (around 12 percent for all-
purpose), forms a crust that’s a little too leathery.
Cornstarch and potato starch on their own are powdery
and pale. Combining flour with cornstarch dilutes the
flour’s protein content, creating a thinner, more delicate
crunch that’s further enhanced by a bit of baking powder.
Finally, to best emulate frying in the oven, you need to
add the potatoes to a fully preheated pan with a layer of
oil in it, so that they sizzle upon contact.
NOTE: These seasoned planks are also great deep-fried.
Follow the recipe as directed through step 3 (skip
preheating the oven and the rimmed baking sheet), then
deep-fry the potatoes in two batches in 2 quarts peanut oil