In a large skillet, heat 2 teaspoons of the oil over moderate heat. Dredge the chicken in the flour, shaking off the excess. Sauté the chicken for 2 minutes per side until golden. Transfer to a plate.
Add the bell pepper and the remaining 1 teaspoon of olive oil and sauté for 3 minutes or until crisp tender. Add to the plated chicken.
Add the sugar to the pan and cook for 3 minutes until caramelized. Add the vinegar and cook for 30 seconds.
Add the orange zest, juice, broth, rosemary and pepper and bring to a boil.
Return the chicken and bell pepper to the pan, reduce to a simmer, cover and cook for 7 minutes or until the chicken is just cooked through. Stir in the cornstarch mixture and boil for 1 minute, stirring, until lightly thickened.
Meanwhile with a small paring knife, peel the oranges. Separate the orange sections from the membranes and stir the segments into the pan. Serve the chicken with the sauce and oranges.