Place the potatoes in pot. Add water until it's an inch or two above the potatoes.
Place the pot over high heat. Bring to a boil.
Reduce the heat to medium, so the potatoes are simmering well but not rapidly boiling.
Cook for 10-20 mintues depending on the size of the potatoes. Insert a probe thermometer it should go in easy enough and record a temperature of 185 degrees.
Drain the water out of the pot. Smash the potatoes with a fork. Add butter, salt, and pepper. It's ready to serve.
If you want to use the potatoes for potato salad, keep whole, and then place into a bowl of ice water. Chill for 2-3 minutes. You can remove the skin with a towel. Then cut into bite sized pieces. Place in the fridge until cold and ready to make your potato salad with.
Notes
Here are the ingredients we like to use to make our potato salads with:
1 pound cooked purple potatoes
1 teaspoon kosher salt
black pepper to taste
½ cup mayo
1 tablespoon yellow mustard
¼ onion, finely diced
two ribs of celery, finely diced
chopped fresh dill to taste (optional)
Cut your potatoes into bite sized pieces, then chill them. Once cold add them to a mixing bowl along with all the other ingredients. Fold with a spatula to combine.