In a large mixing bowl, coat the halved potatoes and thyme sprigs with olive oil, 1/2 teaspoon salt, and 1/4 teaspoon black pepper. Arrange the potatoes in the air fryer basket and place the bacon strips on top. Set the air fryer to 400°F and cook until the bacon turns crispy, about 6 to 12 minutes. Remove the bacon and let it cool on a paper towel before crumbling it into pieces.

Give the potatoes a good shake in the basket, then continue cooking for another 8 minutes. Add the shallots to the basket, toss everything together, and air-fry until the vegetables are golden and tender, another 8 to 12 minutes.

While the vegetables cook, whisk together the balsamic vinegar, whole-grain mustard, and thyme leaves in a large bowl. Once the vegetables are done, transfer them to the bowl, pouring in any drippings from the air fryer basket. Gently toss to combine and fold in the crumbled bacon. Enjoy your dish!