Make the sauce: Put the kimchi, juice, garlic, ginger, brown sugar, gochujang, miso, sesame oil, rice vinegar, lime juice, orange zest, fish sauce and gochugaru in a mixing bowl, and stir well to combine. Taste and adjust salt. Let stand at room temperature for at least 10 minutes (or you can store overnight in the fridge, covered).
Step 2
Bring a large pot of generously salted water to a boil. Add noodles and cook for about 5 minutes, or until cooked through but still firm. Drain in a colander, transfer to a bowl of cold water to cool, then drain again and set aside, covered with a towel.
Step 3
Just before serving, put noodles in a large mixing bowl. Add the sauce, along with cucumber, tomatoes, radishes, scallions and chile (if using) and toss gently to coat. Divide among individual serving bowls. Top each bowl with a halved egg, sesame seeds, cilantro and a squeeze of lime juice.
