Preheat oven to 350°F. Spread chicken breasts in a roasting pan.

Drizzle with 1 Tbsp olive oil and sprinkle with 2 tsp chili powder, 1 Tbsp cumin, 1/2 tsp salt, and a pinch or two of cayenne.

Roast chicken for 30 minutes until cooked through. Let cool, then shred or cut into bite-sized pieces. Set aside.

In a large pot, heat remaining 2 Tbsp olive oil over medium heat.

Add chopped onion and sauté for about 5 minutes until softened. Add garlic and cook for 30–60 seconds more.

Add drained white beans, shredded chicken, chopped green chiles, oregano, 2 Tbsp chili powder, 2 Tbsp cumin, 1/2 tsp salt, and 1/4 tsp cayenne. Stir to combine.

Pour in 4 cups of low-sodium chicken broth. Reserve extra broth to thin later if needed. Bring to a gentle simmer and cook over low heat for 20 minutes.

Remove the pot from heat and let sit for about 5 minutes. With the pot off the heat, stir in 3 cups of shredded cheese, adding 1 cup at a time until melted smoothly. Then stir in 1 cup sour cream.

Return the pot to low heat and gently simmer for 15–20 minutes, stirring occasionally. Add extra chicken broth to reach desired consistency if needed.

For added texture, mash about half the beans and chicken in the pot with a potato masher and stir to combine.

Serve hot with garnishes such as scallions, cilantro, extra sour cream, shredded cheese, and hot sauce on the side.