Place potatoes in a large saucepan and add enough cold water to cover by 1 inch. Bring to a boil, then reduce the heat to medium-high. Boil potatoes for 8-10 minutes, or until the potatoes are fork-tender but not falling apart. Drain the potatoes.

Transfer the cooked potatoes to a large bowl. Drizzle with 1 tablespoon of vinegar and toss gently to distribute the vinegar. Let the potatoes sit with the vinegar for about 10 minutes.

In a small bowl, combine the chopped parsley, remaining 1 tablespoon of vinegar, olive oil, salt, and pepper. Pour over the warm potatoes and toss to coat.

Adjust seasoning to taste, adding a little olive oil or a little vinegar as needed. Serve warm or at room temperature.