In a medium soup pan, heat the coconut oil over medium heat.
Add chicken, garlic, and onion to the oil. Cook until chicken is done.
Stir in ginger, basil, cilantro, mushrooms, pepper flakes, chicken stock, and lemongrass. Stir to combine and bring to a boil.
Reduce heat and simmer on low for 10 minutes.
Remove lemongrass stalks and discard. Stir in lime juice and coconut milk and serve immediately.