Trim steak. Then cut in thirds lengthwise, and slice it crosswise into ¼-inch thick pieces.
In a small bowl, whisk together orange zest, juice, Kikkoman soy sauce, sesame oil, honey, garlic, and red pepper flakes.
In a large, 12-inch nonstick skillet or pan add steak and ½ cup of orange juice mixture. Cook over medium-high heat, stirring often until liquid evaporates and steak has caramelized about 13-15 minutes. Remove steak from skillet and place on a plate.
While skillet is still on medium-high heat, add remaining orange juice mixture to pan. Bring to a low boil and cook about 5 minutes to reduce mixture, stir occasionally and use back of a wooden spoon to break up any caramelized bits on bottom of skillet. Add sugar snap peas and cover. Cook for 2 minutes, or until snap peas are bright green. Uncover skillet and cook, stirring often, until peas are tender and sauce thickens, about 2 minutes. Add steak back to skillet and toss to combine. Serve over rice and sprinkle with green onions.