Heat the vegetable oil in a large skillet or wok over medium-high heat.
Add the chicken pieces and sear until browned on all sides, approximately 5 to 7 minutes.
Remove the chicken from the skillet and set aside.
Add the diced onion to the skillet and sauté until translucent, about 3 to 4 minutes.
Incorporate the minced garlic and grated ginger, cooking for 60 seconds until fragrant.
Stir in the turmeric, salt, and black pepper.
Pour in the coconut milk and fish sauce, deglazing the pan by scraping the bottom with a wooden spoon.
Return the chicken to the skillet and bring the mixture to a simmer.
Reduce heat to medium-low and simmer uncovered for 10 to 12 minutes until the sauce has thickened and the chicken reaches an internal temperature of 165°F (74°C).
Stir in the lime juice and garnish with chopped cilantro prior to serving.