Mulligatawny Soup is a creamy British-Indian chicken soup made with coconut milk, garam masala, curry powder, cumin, coriander, white rice, and a sweet-tart apple. Tender strips of curried chicken and hearty vegetables make it a rich, meal-worthy soup perfect for weeknight dinners.
Heat 1 tablespoon oil in a 4-5 qt stock pot or Dutch oven over medium until shimmering.
Toss chicken pieces with the seasonings and flour and add to pot. Brown chicken on all sides — cooking through completely — and remove to a plate or bowl and set aside.
Add another 1 tablespoon of oil to the pot (still on medium heat). When shimmering, add the onions, celery, and carrots, and saute until softened.
Push the vegetables to one side, and add the remaining tablespoon of oil to the bare spot, heating briefly. Sprinkle the garam masala, curry powder, flour and a generous pinch of salt over the oil, along with the garlic, and stir to form a fragrant paste. Mix into the vegetables, cooking briefly to bloom the spices. Add a splash of the chicken stock and stir to smooth out any lumps formed by the flour and spices.
Pour the remaining chicken stock into the pot and turn the heat to high. Bring the soup to a gentle boil, add the rice, and reduce heat to maintain an active bubbling. Partially cover the pot and cook for 20 minutes (or the time indicated on the rice's packaging).
At the end of the rice's cooking time, reduce heat to low, and add the cooked chicken to the soup. Grate the apple directly over the pot (to catch all the juices). Cook for 5 minutes more. Taste and add salt as necessary.
Add the coconut milk, stirring to mix thoroughly, and let warm through with the residual heat of the soup. Do one final tasting, adding salt and pepper to suit.