Warm Potato Salad with Bacon, Apples & Rosemary

• 1-1/2 lb.Yukon Gold potatoes, peeled, halved lengthwise, and sliced into 1/2-inch half moons (see Choosing the best potatoes for salads)
• 1/4 cup olive oil
• Kosher salt and freshly ground black pepper
• 3 thick or 4 regular slices bacon, cut into 1/2-inch pieces
• 1/2 cup diced yellow onion (1/4-inch dice)
• 1/3 cup apple-cider vinegar (5% acidity)
• 1 sweet-tart apple (like Gala), peeled, cored, and cut into 3/4-inch dice
• 1 Tbs. chopped fresh flat-leaf parsley
• 1-1/2 tsp. chopped fresh rosemary

Heat the oven to 400°F. Put the potatoes in a large bowl and drizzle with 2 tablespoons of the oil. Season well with salt and pepper and toss. Spread the potatoes on a large baking sheet and roast until they're slightly brown and easily pierced with a fork, 15 to 20 minutes.

Meanwhile, heat the remaining 2 tablespoons oil in a large skillet over medium heat. Add the bacon and cook, stirring occasionally, until golden brown, about 10 minutes. Using a slotted spoon, transfer the bacon bits to a paper towel to drain.

Add the onion to the pan, season with salt and pepper, and cook until the onion is softened, 3 to 4 minutes. Add the vinegar, mix well, and then add the cooked potatoes, apple, bacon, parsley, and rosemary. Gently fold everything together until evenly coated. Season with salt and pepper and serve immediately.