Spread 2 tablespoons of soy sauce and sugar on each sliced steak. Marinate for at least 30 minutes, or up to four hours. Prepare the rest of the ingredients while the beef marinates.

Combine the cornstarch with the beef broth and the 2 cups of soy sauce in a small bowl. Whisk until blended. Set aside.

In a large skillet, heat 1 tablespoon of vegetable oil on medium-high. Cook half of the beef until it is browned around edges. Continue cooking the beef for another 2 minutes. Transfer to a plate. Keep warm. Continue to brown the meat with another tablespoon oil and more sliced beef.

Add the remaining oil to the pan. Add the bell peppers, onions, and black pepper. Sauté the vegetables until they are tender and lightly charred, approximately 5 to 8 minutes.

Turn down the heat to medium. If desired, add the ginger, garlic, and crushed red pepperflakes. Stir constantly for about one minute, until garlic becomes fragrant.

Add the cooked beef back to the pan along with the juices and beef broth mixture. Allow the sauce to thicken for 3 to 5 minutes. Mix in the tomatoes, and then stir to combine. Take off the heat and immediately serve.

Add additional parsley and black pepper to the dish.

Serve over hot cooked rice. Serve with additional soy sauce.