Bring an inch or two of water to a boil.
Place meat in freezer for 15 minutes to make it more stable for slicing very thinly.
Peel tangerines or blood orange, scraping away the pith. Drop it into the boiling water for 1 minute; remove and thinly slice. If using dried tangerine and an orange, reconstitute dry peels in warm water and boil the orange peel, pith removed, for 1 minute. Squeeze 1/4 cup blood orange, tangerine or orange juice into a bowl and reserve.
Salt orange-infused water and par-boil broccolini 3-4 minutes. Cold shock and dry the broccolini and discard the water. Chop broccolini into 2-inch pieces.
Whisk up tangerine, blood orange or orange juice with 2 tablespoons soy sauce, 1 tablespoon of sherry and cornstarch.
Slice steak very thin against the grain and toss with marinade. Chill 30 minutes.
Heat 1 tablespoon stir fry oil in a nonstick pan or wok-shaped skillet over high heat. When oil smokes, stir-fry half the beef to brown and caramelize. Remove to plate and repeat with another tablespoon oil and remaining beef. When all of meat is brown and crispy, heat last tablespoon of oil and stir-fry scallion whites, ginger, garlic, chili pepper, peppercorns and sliced tangerine or blood orange or orange peel for 1 minute. Add remaining 3 tablespoons sherry, the light brown sugar, remaining 2 tablespoons soy and the Hoisin and black bean sauces. Heat through; add broccolini and cook 1-2 minutes. Add reserved beef and scallion greens, toss 1 minute and remove pan from heat.
Serve over rice with toppings of choice.