Slice the chicken breast into even 1-inch thick strips.
Place chicken in a bowl with buttermilk and let marinate for at least 15 minutes.
In a shallow dish, whisk together arrowroot powder, garlic powder, onion powder, sea salt, and black pepper.
Remove chicken from buttermilk, letting excess drip off, and dredge thoroughly in the arrowroot mixture.
Heat avocado oil in a large skillet over medium-high heat.
Fry chicken strips for 4-5 minutes per side until the coating is golden brown and the internal temperature reaches 165°F.
In a small bowl, whisk together Dijon mustard, raw honey, and apple cider vinegar until smooth.
Serve the hot, crispy chicken strips immediately with the honey-mustard sauce on the side.