i would not recommend to heat potato salad, no matter what base you use. Best ensure, when boiling your potatoes with skin on and in salt water. Just take a small knife, and when you push the knife into the core of one potato you will not feel any resistance. Then drain off the water and let them cool down and you will see, they always will be perfectly cooked. Note: when you prepare the German versions, your potatoes should be still warm, when you mix them with the beef stock based dressing.
In a perfect world, the potatoes are boiled right the first time (always try to aim for this goal), or you have more potatoes to try again. But the world is NOT perfect. If your potatoes are hard, there is no back-up potatoes, and dinner is SOON, you can, if you must-rinse the potato salad in a collander to remove the mayo/dressings. Pick out the raw potatoes--nuke or reboil, them after a quick chill, recombine to other ingredients and fresh dressing.
Chef Al The Independent Chefs Federation: www.geocities.com/chefsfederation "Trust a Chef who licks his own fingers"--William Shakespeare "Only the pure of heart can make good soup"--Ludwig van Beethoven
I adore potato salad, I probably make it wrong by most peoples standards, but we love it. I either use gourmet tats, cut if needed, not peeled. Or if they are not up to standard, cubed, quite large. Cook them with salt, just so the point a skinny knife point does not feel silly trying to do its essentual job. Drain, I keep it. The water I mean. I keep the "tatoes too.
Meanwhile, consider the 'fridge. I can generally find various coloured bell peppers, red onion, dill pickles and/or gerkins, capers go well, and so does roughly chopped hard cooked egg. Finely chopped celery likes a look in, and even a bit of raw cabbage. The thick white stems and those bits. Blanched cauliflower joins in, with its nose turned up at the raws. (you know about cauliflower don't you.) I never grate anything, just chop small otherwise the juice is lost. I never introduce meat. So uncouth. A bit like wearing gumboots to a wedding.
Now clearly this is not enough. I get involved with sour cream, Mayo, herbs, Curry, Mustard (english) or grain, whatever is available. Make enough acceptable slotch and chuck in the veg and so on, mix enough. Slop onto the still hot potatoes. Put on the lid so it can get a bit of melt on, then turn gently. Letting everything get together in a very close way without upsetting the spuds. Leave it for a few minutes, turn into a bowl you hope is big enough. All the ooze will then be on the top. We serve it sort of warm, on the premise that a spud can only put up with so much, and no more. It is always last cooked. The meat can lay around for half an hour or so, like a Roman Senator, but tatoes are sensitive.