Preheat the grill to medium-high heat.

In a small bowl, whisk together Dijon mustard, honey, olive oil, apple cider vinegar, garlic powder, smoked paprika, salt, and pepper.

Place chicken breasts in a resealable plastic bag or shallow dish and pour the marinade over the chicken. Seal and refrigerate for at least 30 minutes, preferably 1–2 hours.

Remove chicken from the marinade and discard any excess marinade.

Grill chicken for 6–8 minutes per side, or until fully cooked and internal temperature reaches 165°F (74°C).

Serve immediately, garnished with fresh herbs if desired.