Heat olive oil in a large pot over medium heat, then add the cubed chicken. Cook until the chicken is browned and cooked through, about 5-7 minutes. Remove the chicken and set aside.
Add diced roasted peppers and minced garlic to the same pot, sautéing for about 2 minutes until fragrant and slightly softened. You should smell the garlic releasing its aroma, and the peppers turning slightly darker.
Pour in the chicken broth, scraping up any browned bits from the bottom of the pot to develop flavor. Bring the broth to a gentle simmer.
Add the cooked chicken, white beans, and ground cumin to the simmering broth. Stir everything together, ensuring the ingredients are evenly distributed.
Allow the chili to simmer uncovered for about 15 minutes, gently bubbling, until the flavors meld and the broth thickens slightly. The mixture will turn creamy and velvety.
Stir in the sour cream to add richness and a smooth texture to the broth. Mix well until fully combined and heated through, about 2 minutes.
Taste and season with salt and pepper as needed for flavor balance. Ladle the hot chili into bowls and serve immediately.
