This sweet, salty salad is good with a pasta dish or seared pork chops.
Preheat oven to 425 degrees. Line a rimmed baking sheet with foil and place an ovenproof wire rack on top. Place 4 slices thick-cut bacon on rack, sprinkle with brown sugar, and season with ground pepper. Bake until bacon is crisp and glaze is bubbling, 10 to 15 minutes. Drain bacon on paper towels, then roughly chop.
In a large bowl, whisk together vinegar, extra-virgin olive oil, and grainy Dijon mustard; season with coarse salt and pepper. Add bacon and 2 bunches (8 ounces total) frisee, torn into bite-size pieces. Toss well to coat.