01 - Preheat oven to 350°F (175°C). Lightly grease a standard 6-cup muffin tin or line with silicone muffin cups.
02 - Place ramen noodles in a saucepan with boiling water and cook according to package instructions, omitting the seasoning packet. Drain thoroughly and rinse under cold water to stop cooking.
03 - In a mixing bowl, combine soy sauce, sesame oil, mirin (if using), sugar, and sliced green onion. Toss drained noodles in the mixture until evenly coated.
04 - Divide the seasoned noodles evenly between the muffin cups, gently pressing into each cup so the noodles form a base.
05 - In a separate bowl, vigorously whisk together eggs, whole milk, salt, and ground white pepper until uniformly blended.
06 - Pour equal portions of the egg mixture over the noodles in each muffin cup. Sprinkle with toasted sesame seeds, nori flakes, and cheese if desired.
07 - Place muffin tin in the oven and bake for 18 to 20 minutes, or until eggs are set and surface is lightly golden.
08 - Allow muffins to cool in the tin for 5 minutes before gently removing. Serve warm or at room temperature.