For the steak marinade, mix soy sauce and sesame oil. Place steak in bowl and toss to coat. Season with black pepper. Marinate for 30 minutes to 2 hours.
Meanwhile, mix the matchstick-cut vegetables with the remaining ingredients.
In a skillet over medium heat, cook steak for 7 minutes on one side, don’t move the steak for the first 2 minutes to get a good sear. Flip and cook another 5-7 until steak reaches desired doneness. Let rest for 10 minutes before slicing.
In the same skillet, lower heat to medium-low and wipe the pan with a paper towel. Add the matchstick veggies and saute for 2-3 minutes.
To plate, place the veggies on the bottom and sliced steak over them. Garnish with sesame seeds.