1. Preheat oven to 400ºF. Spray baking dish with nonstick cooking spray.
2. Combine maple syrup, country Dijon mustard, Dijon mustard, rice wine vinegar, garlic, salt and black pepper in small bowl and whisk to blend.
3. Arrange chicken thighs in baking dish; brush evenly with olive oil. Spoon maple Dijon sauce evenly over chicken thighs.
4. Bake uncovered for 40 minutes, or until sauce is bubbly and chicken is fully cooked.
5. Remove baking dish from oven; transfer chicken thighs to serving platter, place baking dish on stove top burner.
6. Combine corn starch and chicken broth in small bowl and stir to blend.; add to baking liquid and whisk over low heat for 1 to 2 minutes, or until sauce thickens.
7. Spoon maple Dijon sauce over chicken. Garnish with fresh rosemary.