Season beef medallions generously with black pepper and smoked paprika on both sides. Heat neutral oil in a large skillet over medium-high heat until shimmering. Working in batches of 2-3 medallions, sear for 2-3 minutes per side for a caramelized crust while keeping the center rare to medium-rare. Finish with a pat of butter and transfer to a plate.

Bring beef broth and dashi stock to a gentle simmer in a large pot over medium heat. Add minced garlic and let infuse for 2 minutes. Whisk white miso paste with a ladle of broth in a small bowl until smooth, then whisk back into the pot. Stir in soy sauce, gochujang, and rice vinegar. Taste and adjust seasoning as needed.

Whisk together tahini, heavy cream, and sesame oil in a small bowl until completely smooth, about 1 minute. The mixture should be pourable but rich. Thin with additional cream or water if needed.

Bring a separate large pot of water to a boil. Add all 4 packs of fresh ramen noodles and cook for 3-4 minutes until tender with a slight bite. Drain and divide among four bowls.

Ladle hot miso broth evenly over noodles in each bowl. Arrange seared beef medallions on top in an overlapping pattern. Drizzle generously with creamy sesame sauce. Top with sliced green onions and toasted sesame seeds. Serve immediately while hot.