Gather all your ingredients: shredded chicken, carrots, celery, onion, lemongrass, chicken broth, and garlic. Prepare the vegetables by peeling and slicing the carrots, chopping the celery and onion, mincing the garlic, and bruising or slicing the lemongrass to release its aroma.
Place a large stockpot over medium heat and add a splash of oil. When the oil is shimmering, add the diced onion and sauté until it turns translucent and fragrant, about 5 minutes. You should hear a gentle sizzle and see the onions soften and become slightly golden.
Add the sliced carrots, chopped celery, and minced garlic to the pot. Cook, stirring frequently, until the vegetables are fragrant and slightly softened, about 3 minutes. The mixture will become more aromatic, and the vegetables will start to glisten.
Stir in the shredded chicken and cook for another 2 minutes, allowing the flavors to meld and the chicken to warm through. The mixture should look well combined and heated evenly.
Pour in the chicken broth and add the bruised or sliced lemongrass stalks. Bring the mixture to a gentle simmer over medium heat. You’ll hear a soft bubbling, and the broth will start to steam around the edges.
Reduce the heat to low and let the soup simmer uncovered for 20-25 minutes. During this time, the broth will become fragrant, and the vegetables will become tender but not mushy. The lemongrass will infuse the broth with a bright citrus aroma.
Taste the broth and adjust with salt, pepper, or a squeeze of lemon juice if desired. Remove the lemongrass slices from the pot, discarding them to prevent any woody or overly strong bits from lingering in the soup.
Give the soup a final stir, ensuring everything is hot and well combined. The vegetables should be tender, and the broth clear and aromatic, ready to serve.
Ladle the steaming soup into bowls and enjoy immediately. The fragrant broth, tender vegetables, and savory chicken make for a cozy, satisfying meal.
