Preparation Boil beef and chicken stocks in medium saucepan until reduced to 2 1/2 cups, about 45 minutes. Heat 2 tablespoons olive oil in heavy large saucepan over medium-high heat. Add shallots and sauté until tender, about 4 minutes. Add reduced stock mixture, marmalade and chipotle chilies. Simmer until mixture is reduced to 2 cups, about 5 minutes. Mix 1 tablespoon water and cornstarch in small bowl. Whisk cornstarch mixture into stock mixture. Stir until sauce boils and thickens, about 5 minutes. Season to taste with salt and pepper. (Can be prepared 1 day ahead. Cover and refrigerate.) Preheat oven to 425°F. Sprinkle pork with salt and pepper. Heat remaining 1 tablespoon olive oil in heavy large ovenproof skillet over high heat. Add pork and cook until brown on all sides, about 4 minutes. Transfer skillet to oven and bake until thermometer inserted into pork registers 155°F, about 15 minutes. Let pork rest 5 minutes. Bring sauce to simmer. Slice pork into 1/2-inch-thick medallions; arrange on plates. Spoon sauce over and serve. *Chipotle chilies canned in a spicy tomato sauce, sometimes called adobo, are available at Latin American markets, specialty foods stores and some supermarkets.
Preparation Boil beef and chicken stocks in medium saucepan until reduced to 2 1/2 cups, about 45 minutes. Heat 2 tablespoons olive oil in heavy large saucepan over medium-high heat. Add shallots and sauté until tender, about 4 minutes. Add reduced stock mixture, marmalade and chipotle chilies. Simmer until mixture is reduced to 2 cups, about 5 minutes. Mix 1 tablespoon water and cornstarch in small bowl. Whisk cornstarch mixture into stock mixture. Stir until sauce boils and thickens, about 5 minutes. Season to taste with salt and pepper. (Can be prepared 1 day ahead. Cover and refrigerate.) Preheat oven to 425°F. Sprinkle pork with salt and pepper. Heat remaining 1 tablespoon olive oil in heavy large ovenproof skillet over high heat. Add pork and cook until brown on all sides, about 4 minutes. Transfer skillet to oven and bake until thermometer inserted into pork registers 155°F, about 15 minutes. Let pork rest 5 minutes. Bring sauce to simmer. Slice pork into 1/2-inch-thick medallions; arrange on plates. Spoon sauce over and serve. *Chipotle chilies canned in a spicy tomato sauce, sometimes called adobo, are available at Latin American markets, specialty foods stores and some supermarkets.