In a medium bowl, combine the soy sauce, brown sugar, sesame oil, gochujang, minced garlic, and grated ginger. Add the thinly sliced beef and toss to coat. Let it marinate for at least 30 minutes at room temperature (or up to 2 hours in the refrigerator) for more flavor.
Heat the vegetable oil in a large pan over medium-high heat. Once hot, add the marinated beef in a single layer and cook for 3-4 minutes, stirring frequently until the beef is well browned and cooked through.
Divide the cooked jasmine rice among four bowls. Top each bowl with the cooked bulgogi beef, shredded carrots, and sliced cucumber.
Sprinkle the bowls with sliced green onions, sesame seeds, and fresh cilantro for an added burst of flavor and color.
Enjoy your spicy Korean beef bulgogi bowls hot, and feel free to add extra gochujang on the side for those who like it spicier!