Cook the ramen noodles according to package instructions. Drain and set aside.
In a bowl, combine the sliced beef, soy sauce, sesame oil, gochujang, garlic powder, and ginger powder. Mix well and let it marinate for at least 15 minutes.
Heat the vegetable oil in a large skillet over medium-high heat. Add the marinated beef and cook for about 3-4 minutes, or until browned and cooked through. Remove from the skillet and set aside.
In the same skillet, add the beef broth and bring to a simmer. Stir in the miso paste until dissolved.
Reduce the heat to low and slowly whisk in the heavy cream. Allow the sauce to simmer for about 5 minutes, stirring occasionally. Season with salt and pepper to taste.
Add the cooked ramen noodles to the creamy broth and stir to combine.
Serve the ramen in bowls, topped with the grilled beef, chopped green onions, and sesame seeds.