Hasselback potatoes never fail to get a “wow” at the dinner table. These accordion-shaped potatoes are lovely to look at, and a basting method while roasting ensures that flavor permeates the potato and crisps all the fine edges. Any potato can be prepared this way, including sweet potatoes, which may be the most striking presentation, since they fan out to reveal their orange jeweled flesh while roasting.
To make Hasselback sweet potatoes, choose long, relatively stable, and straight potatoes. The key is to cut as many thin slices as possible, crosswise, along the length of the potato. To do this—without a wayward potato rolling across your cutting board—slice a sliver of each potato lengthwise along its base to stabilize it on a work surface and in the baking dish to prevent any wobbling or tilting. Then place the potato on a work surface with a thin cutting board snugged up on either side of it. With a sharp knife, make narrow incisions crosswise in the potato, approximately 1/8-inch to 1/4-inch thick. The cutting boards will prevent the knife from cutting through the base of the potato. If a few bits break off, no worries; just continue to slice them if you can.
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