Heat a small pot over medium heat. Add sesame oil, garlic, and ginger. Sauté 30 seconds until fragrant—you’re not frying a steak, so keep it gentle.
Stir in the chicken stock, soy sauce, and sugar. Bring to a gentle simmer and let it bloom for 3–5 minutes.
Whisk in miso paste if you’re using it. It should dissolve like magic; no chunky drama allowed.
Add pepper and chili flakes to taste. If you like a milder glow, err on the side of a whisper—they’ll still taste amazing.
Taste and adjust salt or sweetness. If it tastes flat, a tiny extra splash soy or a pinch more sugar will fix it. You’re the boss here.
Pour over your prepared noodles and add any toppings you love. Serve hot and slurp proudly.