A tangerine's skin is so thin that when it's cooked, you can eat the fruit - peel and all. Asian sweet chili sauce is an orange-colored, slightly spicy bottled Thai sauce; it's available in the Asian foods section of some supermarkets. Chinese five-spice powder can be found in the spice section of most supermarkets.
1 tablespoon cornstarch
2 tablespoons Asian sesame oil, divided
1 tablespoon minced peeled fresh ginger
4 small unpeeled tangerines or clementines, cut (with peel) into 3/4 inch pieces
1/4 cup Asian sweet chili sauce
2 tablespoons soy sauce
1/4 teaspoon Chinese five-spice powder
6 baby bok choy, cut crosswise into 1-inch thick ribbons, tough bases discarded
5 green onions, thinly sliced on diagonal, divided
Place pork tenderloin strips in medium bowl; sprinkle with salt and freshly ground black pepper and toss with cornstarch to coat. Heat 1 tablespoon sesame oil in large nonstick skillet over medium-high heat. Add minced ginger; stir 30 seconds. Add pork tenderloin strips; stir-fry until pork is beginning to brown and is almost cooked through, about 3 minutes. Add tangerine pieces; toss 30 seconds. Add sweet chili sauce, soy sauce, and Chinese five-spice powder; boil until sauce in skillet thickens slightly, tossing to blend, about 1 minute. Stir in remaining 1 tablespoon sesame oil, bok choy, and half of sliced green onions. Stir-fry just until bok choy is wilted. 1 to 2 minutes. Season to taste with salt and freshly ground black pepper. Transfer to bowl; sprinkle with remaining sliced green onions and serve.