In a bowl, whisk together the honey, Dijon mustard, whole grain mustard, apple cider vinegar, soy sauce, garlic, salt, pepper, and chicken broth until thoroughly combined.
Add the chicken breasts to the mixture, ensuring each piece is well-coated. Arrange the chicken in a baking dish in a single layer, and tuck the rosemary sprigs between the chicken pieces.
Place the baking dish in the oven and bake for 25 to 35 minutes, or until the chicken is cooked through and reaches an internal temperature of 165°F (75°C).
Remove from the oven and drizzle the chicken with the sauce from the baking dish before serving.
Notes
For juicier chicken with more sauce, cover the pan while baking. For a darker, golden-brown finish with a thicker sauce, bake uncovered.