Place a large pot over medium heat. Add diced bacon and cook until crispy, about 8 minutes. Remove bacon to a paper towel-lined plate to drain.
Add chicken breasts to the same pot and cook in the bacon grease for 3-4 minutes per side, until no longer pink in the center. Transfer to a cutting board.
Add jalapeno to the pot and cook for 1 minute. Add diced tomatoes, beans, tomato sauce, and spices to the pot. Stir to combine. Allow chili to simmer while you dice the chicken.
Add chicken and bacon to the pot. (Reserve some of the bacon if you want to garnish your bowls with it.) Stir to combine. Add sour cream and stir until incorporated.
Simmer chili for 5-8 minutes until bubbling and slightly thickened. Check seasoning and adjust as needed. (I usually add another 1/2 teaspoon of salt now.)
Portion chili into bowls and garnish with green onion. Serve immediately.
Notes
This recipe makes 2 main dish servings or 4 appetizer/side dish servings.