Start by bringing a large pot of salted water to a strong simmer, just below a boil. Be careful not to overcook the potatoes—they should be just fork-tender to hold their shape in the salad. Cut the potatoes into bite-sized chunks and simmer until just fork-tender, about 10-12 minutes. Drain well and let them dry in the colander for a few minutes.

Preheat the oven to 425°F. Toss the potatoes with 3 tablespoons of olive oil, salt, and black pepper, then spread them onto a baking sheet in an even layer. Roast for about 18-20 minutes, flipping once, until crispy and golden brown.

While the potatoes roast, cook the bacon in a large skillet over medium heat until crispy. Remove the bacon and set aside, leaving the rendered fat in the skillet. Slice the onion and fennel before adding them to the skillet with the bacon fat, along with the salt, black pepper, and thyme sprigs. Cook, stirring occasionally, until deeply caramelized, about 15-20 minutes. Deglaze the pan with an extra splash of Smoke and Fire Vinegar, scraping up any browned bits for added flavor. Remove thyme sprigs.

In a large mixing bowl, whisk together the Smoke and Fire Vinegar, whole grain mustard, and remaining olive oil. Stir in the crispy bacon. Add the warm roasted potatoes, caramelized onions and fennel, and sliced scallions. Toss gently to coat everything in the dressing.

Finish with fresh dill and adjust seasoning as needed. Serve warm and enjoy the layers of smoky heat, crispy textures, and herbaceous brightness.