Cook the Potatoes: Add whole, unpeeled potatoes to a large pot and cover with water and two pinches of salt. Bring to a boil, then simmer for about 20 minutes or just until fork tender. Don’t overcook the potatoes. Drain potatoes and let them steam dry for a few minutes. Once cool enough to handle (but still warm), peel the skin off and cut into thin (1/4’’) slices.

Dressing: Heat olive oil in a skillet over medium heat. Add onions and sauté for 3-4 minutes, until soft and translucent. Add broth and bring it to a gentle boil. Once boiling, remove from heat and stir in vinegar, mustard, sugar, salt and pepper.

Combine: Place sliced warm potatoes in a large bowl. Pour the hot onion-broth mixture over the potatoes and gently toss to coat. Cover bowl and rest at room temp for at least 1 hour, stirring once or twice to allow potatoes to absorb a lot of the dressing.

Finish: Stir in 2 Tablespoons oil to (to give a glossy, creamy texture). Taste and season with more salt and pepper if needed. Garnish with fresh chives before serving.

Serve warm or at room temperature.