Start by cutting the boneless chicken into bite-sized pieces, about 1-inch cubes. This size will help the chicken cook evenly and quickly.
Place the cut chicken pieces in a large mixing bowl. Add 2-3 tablespoons of plain yogurt, a teaspoon of garlic and ginger paste, and squeeze in the juice from half a lemon. The yogurt will help tenderize the chicken, while the garlic, ginger, and lemon add flavor.
Sprinkle in a tablespoon or two of tikka chicken spice mix (if you have it; otherwise, use a mix of ½ teaspoon each of turmeric, paprika, cumin powder, coriander powder, garam masala, and Kashmiri chili powder for a similar taste).
Mix everything thoroughly so the chicken pieces are well-coated with the yogurt, spices, and lemon juice. Cover the bowl and let the chicken marinate for at least 30 minutes, or up to an hour if you have more time. This marination helps infuse the chicken with flavor.
In a large pot, heat 1-2 tablespoons of cooking oil over medium-high heat.
When the oil is hot, add the marinated chicken pieces in a single layer. Let them cook without stirring for a couple of minutes to allow a golden crust to form
Flip the chicken pieces and cook until golden brown on both sides. The goal here is to sear the chicken, not to cook it all the way through. Once browned, remove the chicken from the pot and set it aside on a plate.
In the same pot, add a little more oil if needed. Add 1 finely chopped onion and cook it over medium heat, stirring occasionally. Sauté the onion for about 5 minutes, or until it becomes soft and translucent. This will add sweetness and depth to the soup base.
Take 3-4 tomatoes and grate them, or finely chop them if grating isn’t an option.
Add the grated tomatoes to the pot with the onions. Stir and let the tomatoes cook for about 5 minutes with the lid off, until they break down and blend into the onions, forming a thick, fragrant gravy. If you can't grate the tomatoes, you can still use a stick blender to smooth out the soup.
Pour in chicken broth to add depth and richness to the soup. Then add ½ cup of heavy cream, stirring gently to combine. The cream will add a smooth, luxurious texture to the soup.
Return the seared chicken pieces to the pot. This step allows the chicken to finish cooking in the flavorful broth.
Sprinkle in a little more of the tikka chicken spice mix or a small pinch of each spice you used in the marination (turmeric, paprika, cumin powder, coriander powder, garam masala, and Kashmiri chili powder) to enhance the flavor.
Lower the heat to medium or medium-low and let the soup simmer for about 10 minutes. This will allow the flavors to meld together, and the chicken will absorb the spices.
Before serving, do a quick taste test. Add a pinch of salt or an extra squeeze of lemon juice if needed, to balance the flavors. Once it tastes just right, your Tikka Chicken Masala Soup is ready to be served.