Heat vegetable oil in a large skillet or deep pan over medium-high heat.
Add the diced onion and sauté for 5 minutes until translucent and soft.
Stir in the garlic and ginger, cooking for 60 seconds until fragrant.
Add the cubed chicken to the pan and sear until browned on all sides, approximately 5-7 minutes.
Incorporate the curry powder, turmeric, and garam masala, stirring continuously for 1 minute to toast the spices.
Pour in the mango puree and coconut milk, stirring to deglaze the pan and combine ingredients.
Reduce heat to low and simmer for 15 minutes until the sauce has thickened and the chicken reaches an internal temperature of 74°C (165°F).
Season with salt according to preference.
Remove from heat and garnish with fresh cilantro before serving.