In a bowl, combine the sliced beef, soy sauce, gochujang, sesame oil, garlic, and ginger. Marinate for at least 20 minutes.

Heat vegetable oil in a grill pan over medium-high heat. Grill the marinated beef for about 3-4 minutes on each side or until cooked to your liking. Remove from heat and set aside.

In a large pot, combine beef broth, water, brown sugar, and rice vinegar. Bring to a boil.

Add the instant ramen noodles to the boiling broth and cook according to package instructions, usually about 3-4 minutes.

Once the noodles are cooked, reduce the heat to low and stir in the heavy cream. Mix well until creamy and heated through.

Season the ramen with salt and pepper to taste.

Serve the ramen in bowls, topped with grilled beef, chopped green onions, and sesame seeds.