Place the whole, unpeeled potatoes in a large pot and cover them with cold water. Add a generous pinch of salt, then bring the pot to a boil. Lower the heat and simmer for about 20 minutes, or until a fork slides in easily. After that, drain the potatoes well.

Let the potatoes cool just enough so you can handle them. Keep them warm. Peel them if you like, then slice them 1/4 to 1/2 inch thick and place the slices in a large bowl.

Cook the bacon in a large skillet over medium heat until crisp, about 8 to 10 minutes. Move it to a paper-towel-lined plate and crumble it once it cools. Leave the bacon drippings in the pan.

Add the vegetable oil and sliced onion to the drippings and cook for about 5 minutes, until the onion turns soft.

Stir the red wine vinegar, beef broth, and sugar into the skillet. Bring the mixture to a gentle boil so the sugar dissolves and the flavors blend. Taste the dressing and adjust with a little salt and pepper if needed.

Gently fold the potato slices into the dressing, along with half of the crumbled bacon and half of the herbs. Stir carefully so the potato slices stay whole.

Warm everything through for a few minutes, then top with the rest of the bacon and herbs. Let the salad rest for 15 to 20 minutes so the potatoes can absorb the dressing, then serve it warm.