There are a few ways to thicken your chili. You can use less chicken broth. If lessening the chicken broth in this White Chicken Chili recipe, I suggest using 3 cups and adding more if needed. There should be enough liquid in the pot for the chicken to cook in. You can also add more tomato paste or more beans. Additionally, thicken the chili by adding cornstarch or flour. To do this, remove some of the liquid from the pot. Add in 1 tablespoon of cornstarch or flour. Whisk together. Add back to the chili. Bring the chili to a boil and turn down to a simmer to let the chili thicken.