In a medium saucepan, bring the low-sodium chicken broth to a boil over medium heat.: As the liquid heats you will notice steam rising and small bubbles forming along the edges, a sign the broth is approaching a full boil; the aroma will shift from muted to savory, filling the kitchen. Bringing the broth to a boil concentrates its aromatics and prepares it to cook the ramen noodles quickly. A common mistake is overheating so the broth roils, which can overcook the noodles and scramble the egg when added, so aim for a lively but controlled boil and reduce heat if the pan seems too vigorous.
Add the ramen noodles and cook according to the package instructions, about 3 minutes, until tender.: When the ramen noodles hit the hot broth you will hear a soft bubbling and see them soften and separate; gently stir to prevent clumping, watching the strands turn translucent at the edges and then uniformly tender. This short cook preserves bite, and following package timing prevents mushy texture. Overcooking is the usual pitfall here, so check for doneness early, tasting a strand to ensure it has a pleasant spring.
Lower the heat to a gentle simmer. Stir gently and slowly drizzle the lightly beaten egg into the swirling broth to form silky egg ribbons.: At a gentle simmer you will see slow moving currents rather than boiling turbulence, which helps the egg set into delicate ribbons as it meets the broth. Use a spoon or fork to create a swirl, then drizzle the beaten egg in a thin stream; the ribbons will poach almost instantly, offering a glossy, silky texture. If the broth is too hot the egg will break into flakes, and if you pour too quickly the ribbons will clump, so move slowly and keep the temperature steady.
Stir in the soy sauce to blend all the flavors.: After the egg has formed ribbons, the aroma becomes richer and more layered; adding the measured teaspoon of soy sauce deepens the umami and balances the mild broth. Stir briefly to incorporate, noticing how the surface sheen shifts and the soup’s flavor rounds out. A common error is adding too much too soon, which can push the bowl into an overly salty profile, so taste and adjust cautiously.
Pour the soup into a bowl and garnish with chopped chives if using. Serve hot.: As you ladle the soup, steam will rise and the glossy egg ribbons will float among the tender ramen noodles ; sprinkle the chopped chives for a fresh, green contrast in both color and scent. Serve immediately to enjoy the ideal temperature and texture, since the noodles will continue to soften if left standing. The main mistake here is delaying service, which leads to a loss of the delicate texture that makes this bowl special.