In a large skillet, heat the vegetable oil over medium heat. Add the chopped onion and sauté until translucent, about 5 minutes.

Stir in the minced garlic and ginger, cooking for another minute until fragrant.

Add the cumin, coriander, garam masala, turmeric, and chili powder. Stir well and cook for 1-2 minutes.

Pour in the tomato sauce and bring to a simmer. Cook for 5 minutes, allowing the flavors to meld.

Add the chicken pieces to the skillet, stirring to coat them in the sauce. Cover and cook for 15-20 minutes, or until the chicken is cooked through.

Stir in the heavy cream and season with salt and pepper. Simmer for an additional 5 minutes.

For the garlic naan, in a bowl, combine the flour, baking powder, salt, and sugar. Gradually add warm water and yogurt, mixing until a dough forms. Knead for 5 minutes until smooth.

Cover the dough with a damp cloth and let it rest for 30 minutes.

Divide the dough into 4 equal pieces and roll each piece into a flat oval. Brush each naan with melted butter and sprinkle with minced garlic and parsley.

Heat a skillet over medium-high heat. Cook each naan for about 2-3 minutes on each side until golden brown and cooked through.

Serve the butter chicken hot, garnished with fresh cilantro, alongside the garlic naan.