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Merrill is a co-founder of Food52.
If you're cooking small potatoes, or if you cut larger potatoes into 1-2-inch chunks, they should take 15-20 minutes once you've brought the water to a simmer. Start with the potatoes in cold water, and don't forget to salt the water!
Kristen W. is a trusted home cook.
Merrill, why do you start the potatoes in cold water? I know to do this but have never thought to ask why until just now.
To cook them evenly. If you put them in boiling water the outside will over cook before the interior cooks.
Sarah is a trusted source on General Cooking.
Beyond the guidance above - "until they're done". Test by inserting the tip of a knife. If the potato sticks to the knife, it's not cooked. If it falls off after 5-6 seconds resistance it's par-boiled (almost there), if it falls away after a second or two you're almost perfect, and if it doesn't stick at all it's well done to overcooked.
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