In a bowl, mix yogurt, tikka masala, and ginger-garlic paste.
Add chicken pieces to the marinade and coat well. Marinate for at least 1 hour.
Heat oil in a pan over medium heat.
Add chopped onions and sauté until golden brown.
Stir in the marinated chicken and cook until browned.
Add crushed tomatoes and simmer for 15 minutes.
Pour in coconut milk and stir well.
Season with salt and simmer for another 10 minutes.
Garnish with fresh cilantro before serving.
Serve hot with rice or naan.