I start by cubing the raw chicken breast into bite-sized pieces so it cooks evenly later on. Then I puree the onion in a blender or food processor until smooth, which keeps the texture of the finished chili nice and creamy. Mincing the garlic fresh at this stage makes a noticeable difference in flavor once everything cooks together.
Next, I add the chicken broth, cubed chicken, pureed onion, garlic, beans, corn, green chilies, and all the dry spices into one large gallon freezer bag. I press out as much air as possible before sealing it, since that helps the chili freeze flat and thaw faster. This is the point where your frozen chicken chili is officially freezer-ready.
I always lay the sealed bag flat on a baking sheet in the freezer until it's solid. Freezing it flat lets me stack multiple bags later, which is a game changer if you're meal prepping several dinners at once. Once frozen solid, you can stand the bags upright to save even more freezer space.
The night before I want to cook it, I set the frozen bag into a large bowl in the fridge to thaw safely overnight. The bowl catches any condensation or leaks so I don't wake up to a puddle. By morning, the chili base is fully thawed and ready to go straight into the slow cooker.
I pour the thawed contents into my slow cooker, give it one good stir, cover it, and cook on high for about 6 hours. The whole house smells amazing by the time it's ready, and the chicken turns out incredibly tender. This is the easiest part of the entire meal prep white chicken chili process.
Once the 6 hours are up, I stir in the fresh lime juice first, followed by the sour cream, mixing until everything is fully combined. I cover it again and let it cook for another 30 minutes so the flavors meld together. This final step is exactly what makes it a true creamy white chicken chili rather than a plain soup.