Cook rice according to package directions.
Heat oil in a large pot on medium heat.
Add butter, onion, garlic, and ginger and saute until translucent.
Add the chicken tenderloins to the pot and stir well.
Add the crushed tomatoes, cumin, cardamom, cayenne pepper, black pepper, paprika, turmeric powder, chili powder, sugar, and salt and stir well.
Cover and simmer stirring often for about 20 minutes.
After the sauce has thickened, stir in the heavy cream and bring the sauce back to a simmer.
Begin to shred the chicken in the sauce.
Transfer to a serving dish.
Serve over rice, garnish with sliced green onion and a piece of naan bread on the side.