In a bowl, combine the chicken with salt, garlic powder, sweet paprika, curry powder, and Greek yogurt. Let it marinate for at least 30 minutes.

In a large skillet, heat vegetable oil over medium-high heat. Add the marinated chicken and cook until browned and cooked through. Set aside.

Use the same skillet, adding butter. Sauté the minced garlic and diced onion until they turn translucent.

Stir in the tomato sauce, sugar, salt, and black pepper. Bring everything to a simmer, then reduce the heat.

Add heavy cream, cayenne pepper (if using), garam masala, and an additional curry powder. Let it cook on low for about 10 minutes.

Just before serving, stir in an additional tablespoon of butter for that extra richness.

Ladle the butter chicken over rice or with naan, garnishing with freshly chopped parsley for a vibrant finish.