In a mixing bowl, combine soy sauce, brown sugar, sesame oil, rice vinegar, garlic, ginger, and black pepper. Whisk until well combined.

Add the flank steak to the marinade, ensuring it is fully coated. Cover and refrigerate for at least 15 minutes.

Rinse the jasmine rice under cold water until the water runs clear.

In a rice cooker, combine the rinsed rice and water. Cook according to the rice cooker instructions.

Preheat the grill to medium-high heat. Remove the steak from the marinade and discard the marinade.

Grill the steak for about 4-5 minutes on each side for medium-rare, or until desired doneness. Let it rest for 5 minutes before slicing.

In a small bowl, mix together mayonnaise, Sriracha, lime juice, and garlic powder until smooth. Adjust the spice level to taste.

In each bowl, add a serving of rice, sliced grilled steak, and top with green onions, kimchi, and sesame seeds.

Drizzle with the spicy cream sauce before serving.