1Place potatoes into a large pot and cover with lightly salted water; bring to a boil. Reduce heat to medium-low and simmer until tender, 10 to 15 minutes; drain.
2Whisk vinegar, olive oil, mustard, basil, salt, and pepper together in a large bowl; add the potatoes and onion. Toss gently to coat. Let stand until cool, about 30 minutes.
3Fold blue cheese and chives into potato salad until blended.
Footnotes
Tip
Aluminum foil helps keep food moist, ensures it cooks evenly, keeps leftovers fresh, and makes clean-up easy.