Peel the ginger and slice into thin coins, then mince the garlic and thinly slice the onion.
Peel the chayote, remove the inner seed, and cut into bite-sized wedges.
Heat the coconut oil in a medium pot over medium heat and sauté the ginger, garlic, and onion until the onion is translucent and the ginger is fragrant.
Add the cubed chicken breast to the pot and cook for 3-4 minutes until the exterior is lightly browned.
Pour in the chicken broth and bring the mixture to a gentle boil, then reduce heat to a simmer.
Add the chayote wedges to the broth and simmer for 10-12 minutes until the vegetable is fork-tender.
Stir in the fresh spinach, fish sauce, sea salt, and black pepper, allowing the spinach to wilt for about 1 minute.
Place the cooked brown rice in a deep bowl and ladle the hot chicken and vegetable broth over the top before serving.