Preheat oven to 400 f.
In a large bowl, whisk together yogurt, garam masala and salt. Then add cubed chicken thighs and mix well. Place on a baking sheet and roast for approximately 25 minutes.
In a large pan over medium high heat, add oil and saute onions, garlic and ginger for about 4-5 minutes. Then add garam masala, paprika, turmeric, cumin and toast for 1 minute.
Next add crushed tomatoes and water and simmer for 8-10 minutes or until thickened. Then blend (if desired) and add cooked chicken, butter and heavy cream. Season to taste with salt and stir to combine.
Then serve with steamed rice and garnish with cilantro.
Enjoy!