In a bowl, mix chicken chunks with salt, garlic powder, paprika, curry powder, and Greek yogurt. Make sure all the chicken pieces are coated well. Cover the bowl and let marinate for at least 30 minutes.

Heat the vegetable oil in a large pan over medium heat. Once hot, add the marinated chicken pieces. Cook the chicken until it is golden brown on all sides, about 5-7 minutes. Remove the chicken from the pan and set aside.

In the same pan, add 2 tablespoons of butter and let it melt. Once melted, add the minced garlic and diced onion. Sauté until the onion is soft and translucent, about 5 minutes.

Add the tomato sauce to the pan along with the sugar, 1 teaspoon of salt, and black pepper. Stir everything together and let it simmer for about 5 minutes.

Return the cooked chicken back to the pan. Pour in the heavy cream and add the cayenne pepper if you like a bit of heat. Stir to combine and let everything simmer for another 5-10 minutes.

Stir in the garam masala and an extra ½ teaspoon of curry powder. Let it rest for a few minutes off the heat.

Garnish with freshly chopped parsley and serve hot with naan bread or steamed rice.