How to Make It
Cook bacon in a medium-size nonstick skillet over medium, turning occasionally, until crisp, about 8 minutes. Transfer to a plate lined with paper towels, reserving drippings in skillet. Chop bacon; set aside. Carefully pour 2 tablespoons drippings through a fine mesh strainer into a small heatproof bowl (discard solids and remaining drippings). Set aside.
Preheat grill to medium-high (400°F to 450°F). Whisk together vinegar, shallot, mustard, thyme, and chives in a medium bowl. Whisk in reserved drippings and 2 tablespoons of the olive oil until smooth and combined. Stir in pepper; set aside.
Toss together asparagus, salt, and remaining 1 tablespoon olive oil in a large bowl. Place asparagus on oiled grates; grill, uncovered, turning often, until slightly charred and tender, 2 to 5 minutes (depending on the size of your asparagus). Transfer to a serving platter; drizzle with vinaigrette, and sprinkle with chopped bacon.