In a large bowl, combine the chicken pieces with the yogurt, garlic, ginger, garam masala, turmeric, cumin, chili powder, and salt. Stir until the chicken is thoroughly coated, cover with plastic wrap, and let marinate for at least 30 minutes. If possible, let it sit overnight in the refrigerator for maximum flavor.
Once the marinating time is up, heat 1 tablespoon of olive oil in a large skillet over medium heat. Add the chicken pieces, searing them until they are browned on all sides, which should take about 3 minutes. It’s important to not overcrowd the pan to ensure even cooking. If needed, do this in batches, adding more oil as necessary. Once browned, set the chicken aside on a plate to keep warm.
In the same skillet, add 3 tablespoons of butter and let it melt over medium heat. Toss in the sliced onion and cook for about 5 to 7 minutes, stirring occasionally. You want the onions to become soft and start to caramelize, scraping any browned bits from the bottom of the pan.
Next, add the garlic, ginger, cumin, and garam masala. Cook for about 30 seconds until the spices become fragrant.
Stir in the crushed tomatoes, chili powder, cayenne pepper (if using), and salt. Allow the mixture to come to a slight simmer, and let it cook for about 10 minutes. You'll notice the color deepening to a rich red, and the flavors will start to meld together beautifully.
Remove the skillet from heat and carefully transfer the mixture into a blender. Blend until smooth, and then pour it back into the skillet over low to medium heat.
Gradually stir in the heavy cream and sugar, mixing until everything is combined and creamy.
Return the cooked chicken (and any juices) back into the skillet. Stir to combine, and let the sauce come to a gentle simmer, stirring frequently. This is where the magic happens as the butter you set aside will be added in the final step.
Finally, add the remaining 3 tablespoons of butter and allow it to melt into the sauce as you stir, creating a silky texture. Once everything is heated through, your Indian Butter Chicken Recipe is ready to serve!
Serve warm with basmati rice and warm naan bread. Enjoy the delightful flavors!