Preheat the oven to 375 degrees.

Mince 1 onion and 1 tablespoon of garlic. Set the onion and garlic aside for a minute.

Cube 1 and a half pounds of skinless boneless chicken breasts and place the pieces in a large bowl.

Pour 2 tablespoons of vegetable oil over the chicken and mix well.

Season the chicken with 2 tablespoons of tandoori masala and spread it on the baking sheet.

Bake the chicken for 12 minutes or until it's no longer pink in the center.

Remove the chicken from the oven and cover with foil while you prepare the sauce.

Take out 1 cup of butter. Place the skillet over medium heat and add a few tablespoons of butter.

As the butter melts, add the onion and the garlic. Cook slowly and stir them until the onions are caramelized into a dark brown color. This will take about 15 minutes. Remove the onions from the heat.

Place a large saucepan over medium-high heat. Put the remaining butter in the saucepan.

Add 1 can of tomato sauce (15 ounce), 3 cups of heavy cream, 2 teaspoons of salt, 1 teaspoon of Cayenne pepper and 1 teaspoon of garam masala.

Stir the mixture and bring it to a simmer. Then reduce the heat to low and cover the saucepan.

Simmer the sauce for 30 minutes. Stir it occasionally. Then add the caramelized onions and baked chicken pieces.

Simmer everything for another 5 minutes and serve.