Combine the broth, preserves, orange juice, lemon juice, zests, cinnamon and cloves in a saucepan and mix well. Bring to a boil over medium-high heat. Boil for 8 minutes or until mixture is reduced to 1 1/2 cups. Stirring occasionally.
Whisk the port and cornstarch in a small bowl until blended. Whisk the port mixture, marmalade and chili sauce into the broth mixture. Bring to a simmer over medium heat, whisking constantly. Simmer for 5 minutes or until the flavors blend and the sauce is slightly thickened. Season with red pepper flakes, salt and pepper. Serve warm or at room temperature.