In a large mixing bowl, combine the marinade ingredients—Greek yogurt, lemon juice, turmeric, garam masala, garlic paste, ginger paste, and salt. Mix everything thoroughly until you have a smooth, well-blended marinade. Add the chicken pieces and use your hands or a spoon to coat each piece evenly. Make sure every piece is fully covered, as this is what will tenderize the chicken and infuse it with flavor from the inside.

Cover the bowl and let the chicken rest for at least 30 minutes at room temperature, or ideally refrigerate it for a few hours if you have time. The longer it marinates, the deeper the flavor and the more tender the chicken will become. If refrigerated, take it out 10–15 minutes before cooking so it isn’t too cold when it hits the pan.

Heat a large pan over medium heat and add a small amount of oil. Once the oil is hot, add the marinated chicken pieces one by one, leaving excess marinade behind in the bowl. Cook the chicken for about 6–8 minutes, turning occasionally, until it is lightly browned on the outside. You don’t need to cook it fully at this stage—it will finish cooking later in the sauce. Once browned, remove the chicken from the pan and set it aside.

In the same pan, add butter and let it melt over medium heat. Add the finely chopped onions and sauté them slowly, stirring occasionally, for about 6–8 minutes until they become soft, translucent, and slightly golden. This step builds the base flavor of the curry, so take your time and don’t rush it.

Pour in the tomato puree and stir well, scraping the bottom of the pan to lift any browned bits left from the chicken. Let the mixture cook for about 8–10 minutes, stirring occasionally, until it thickens and the color deepens to a rich red. You’ll also notice the oil starting to separate slightly from the sauce—this is a good sign that it’s cooked properly.

Add the spices—cumin, paprika, garam masala, chili powder, and salt—and mix thoroughly into the tomato base. Let the spices cook for 1–2 minutes so they bloom and release their full aroma. Stir continuously during this step to prevent burning and to evenly distribute the flavors.

Reduce the heat to low and slowly pour in the heavy cream while stirring continuously. This helps create a smooth, silky sauce without curdling. Mix until the sauce becomes creamy, rich, and uniform in texture. If it looks too thick, you can add a small splash of water or broth to adjust the consistency.

Return the partially cooked chicken to the pan along with any juices it released. Stir gently to coat all the pieces in the sauce. Let everything simmer on low heat for about 10–15 minutes, stirring occasionally, until the chicken is fully cooked and tender. The sauce will thicken slightly and cling beautifully to the chicken, creating that classic butter chicken texture.