1. In a small bowl, whisk together orange juice concentrate, lemon juice, vinegar, cinnamon, nutmeg, and broth. Set aside.
2. Heat a large nonstick skillet over medium heat. Once it's hot, pour in oil and swirl pan to coat. If the oil smokes, throw it out and start over at a lower temperature. Sear chicken on both sides until nearly cooked through, about 2 minutes per side. Remove chicken to a plate.
3. Pour orange-balsamic mixture into the skillet. Increase heat to medium-high.Cook, stirring occasionally, until reduced by half, about 3 minutes. Mix cornstarch with 1 tsp. of the water until blended, then add to sauce and stir well.
4. Return chicken to skillet. Cook on both sides until cooked through, 2 to 3 minutes, occasionally spooning sauce over the chicken as it cooks. Transfer chicken to a serving platter and tent with foil; pour any remaining sauce into a small bowl.
5. Rinse out skillet. Add spinach and remaining 1 Tbsp. water and cook over medium heat just until wilted, 2 to 3 minutes. Mound spinach next to chicken and drizzle sauce over both. Serve immediately.
Source: Fresh Magazine September, October 2010