Gather all your ingredients and set your workspace for easy prep.
In a large heavy-bottomed pot, heat a small amount of oil over medium heat. Add sliced garlic and ginger, sautéing until fragrant—about 2 minutes—until golden and aromatic.
Pour in the chicken broth and bring to a gentle simmer. Add lime juice and fish sauce, stirring to combine. Let this simmer for about 10 minutes to meld the flavors.
While the broth simmers, thinly slice the chicken breasts and chop the chilies, cilantro, and Thai basil. This helps everything come together quickly later.
Add the sliced chicken and chilies into the simmering broth. Cook for about 5 minutes, or until the chicken turns opaque and is just cooked through.
Taste the broth and adjust the seasoning with more lime juice, fish sauce, or chilies if desired. The broth should be bright, slightly tangy, and spicy.
Remove from heat and ladle the hot soup into bowls. Garnish generously with chopped cilantro and Thai basil for a burst of fresh herbaceous aroma.
Squeeze a fresh lime wedge over each bowl and serve immediately, enjoying the vibrant flavors and fragrant, steaming broth.