Prep the chicken: Pat the chicken dry.
If using breasts, slice horizontally to make cutlets for faster, even cooking. Season both sides with salt, pepper, garlic powder, onion powder, and smoked paprika.
Mix the sauce: In a small bowl, whisk the broth, Dijon, whole-grain mustard, honey, and vinegar or lemon juice. If you like a thicker glaze, whisk in the cornstarch until smooth.
Sear the chicken: Heat a large nonstick skillet over medium-high.
Add the oil. Sear the chicken 3–4 minutes per side until golden and just cooked through (internal temp 165°F/74°C). Remove to a plate.
Build flavor: Reduce heat to medium.
Add the minced garlic to the skillet; stir 20–30 seconds until fragrant. Pour in the sauce mixture, scraping up browned bits. Simmer 2–3 minutes until slightly thickened and glossy.
Coat and finish: Return chicken and any juices to the pan.
Spoon sauce over the pieces and simmer 1–2 minutes to coat well. Taste and adjust salt, pepper, or a splash more vinegar if you want extra tang.
Garnish and serve: Sprinkle with chopped parsley or chives. Serve with steamed green beans, roasted broccoli, a light salad, or cauliflower rice.
For carbs, try quinoa or brown rice.