In my opinion, the quality of potato salad has much more to do with the potatoes then the dressing. If a potato is mushy or mealy, no preparation can turn it into a good salad. On the other hand, a potato done the way I like it has a dense, waxy texture that is so nice, it can be a great pleasure to eat completely undressed, or with just a sprinkle of salt. Once you've achieved a potato like that, the journey to a great salad, via many possible dressings, seasonings, and additions, is short.
So most of this piece will be devoted to explaining how I avoid the mealiness and get the waxiness. It's not difficult, as long as you follow these simple rules:
1. use the right potato
2. don't refrigerate it before or after cooking
3. cook just until a thin tool, when inserted, meets no hard parts in the centre
4. don't pare, cut or peel until cooked and cooled
Regarding varieties, I've mainly had bad results with russet, fingerling, and purple potatoes, and good results with Yukon Gold, PEI, and white. But the ones I find most reliable are redskins, any size. If they've started to sprout or are no longer rock-hard, it's not really a problem.
Refrigerating potatoes, either before or after cooking them, for some reason seems to destroy good texture. So after buying your potatoes, do not refrigerate. Store in a cool, dark place, where a little air can get to them, until using.
Avoiding refrigeration after cooking means that you can't make your salad far ahead of time. So don't make it, stick it in the fridge, and then serve it later. Even if you let it come back to room temperature, it will still have a mealy texture.
However, you CAN boil your potatoes in advance, because cooked, un-peeled potatoes can stay out of the fridge at least a day. Your potato salad will of course be best if you make it shortly after cooking. But if you want to do some of your work ahead of time, boil the potatoes, let them sit uncovered for several hours, even overnight, and then cut and dress them at the last minute.
Begin by rinsing the potatoes. If there are crusty, black spots on the skin, scrub these off with a brush or abrasive sponge. You don't need to get every last spot; they will soften and be lost in the final product.
Part of the key to the waxy texture, I've read, is letting steam remain and condense in the potato after it has cooked. So don't pare, peel, or cut your potatoes before cooking, or else steam will escape from them.
Put your potatoes in the smallest pot that will hold them, to save water and energy. Cover with water and bring to the boil, with the lid on. Then turn down to simmer, covered. I usually don't salt the cooking water. It may be that salting the water leads to a tastier result then merely salting the dressing, but I haven't experimented enough to know.
The potatoes are done when a small, thin knife, skewer, or fork goes in without finding hardness in the centre. Their skins may have begun to split, and they will give a little without falling apart when gently pinched. To avoid overcooking, start testing the potatoes before you think they're done, but don't puncture them too many times, or steam will escape, and they may break.
Cooking time depends mainly on the size of potatoes. Golf-ball sized ones may be done after 10 or 15 minutes of simmering. If you have different sizes, test and remove smaller ones first, letting the larger ones cook longer. The used cooking water often has a nice taste and can be saved for making soups or stews.
After cooking, don't cut or peel the potatoes until their steam has condensed. They don't have to cool all the way to room temperature; warm potato salad is actually lovely. But let them sit out of the water and away from the stove, at least until they are comfortable to hold. This will take about 25 minutes, depending on the potatoes' size and the temperature of the air.
You can now finally remove any eyes, sprouts, or blemishes, using a paring knife or your fingernail. I never peel potatoes because I've been told the skin is rich in nutrients, I like how it tastes, and I don't like to waste food. But if you want a very clean, delicate salad, go ahead.
Cut the potatoes into bite size chunks or slices, large enough to not fall apart during mixing. The cut surfaces should be smooth and almost shiny. And you may see thin lines of slime stretch between the slices when you separate them. This is the sign of a perfectly chosen, handled, and cooked potato! If you're working with fresh ingredients, there is almost nothing you can do to ruin it now.
There's no limit to the good things you can do with a dense, waxy, cooked potato. Here are some of my favourite preparations, starting with the simplest.
- just a sprinkling of salt
- salt and sour creme or creme fraiche
- salt and olive oil
- salt, olive oil, white or freshly ground black pepper, and vinegar or fresh lemon juice
- salt, olive oil, pepper, vinegar or lemon, apples, and chopped celery (this recipe is from my parents' Norwegian friend, Lise Striar)
- mayonnaise, and maybe a bit of salt
- mayonnaise, pickles or capers, and chopped fresh herbs
- salt, vinegar, pepper, ethically raised bacon, mayonnaise and/or the fat released during cooking the bacon, medium-cooked ethically raised eggs, a bit of onions or chives, and capers or chopped pickles (this recipe comes from my former wife's German grandmother)
When making any potato salad, don't over-mix, or the potatoes will start mashing into the dressing, making it pasty.
I don't always use salt, but when I do, I often go pretty heavy on it. The mildness of potatoes can absorb a lot of salt.
When using vinegar in potato salad, I usually avoid the heavy colour and flavour of balsamic, in favour of the lightness of wine or even white vinegar.
I prefer brined, rather than the standard vinegar-cured pickles. They come in a cloudy liquid, and Bubbies is an excellent brand.
When using store-bought mayonnaise, unless it already tastes sweet, I often add a pinch of sugar. Hellman's brand in particular has a slight harshness I like to offset with a little sugar or honey. I never, ever use low-fat mayonnaise or sour cream for anything. Yuck!
I love making mayonnaise from scratch, which I usually blend with plenty of mixed fresh herbs during the warm months, or chipotle during the cold. Both go beautifully with potatoes.
One of my favourite potato salads involves just potatoes, mayonnaise (store-bought is fine), chopped fresh lemon-thyme, and pickles. Lemon-thyme is a variety of thyme found more often in gardens than in stores. For two cups of sliced potatoes, I'd use about a third cup mayonnaise, a half teaspoon of chopped lemon-thyme, and a half cup chopped pickles.