Creamy White Chili

Where I used to work we would have pot-lucks every so often. My boss's wife brought this chili & we all loved it. Here is the recipe:

1 pd boneless, skinles chicken cut into 1/2 inch cubes
1 med onion, chopped
1 1/2 tsp garlic powder
1 Tbsp vegetable oil
2 cans great northern white beans, rised & drained
1 can white hominy (optional)
1 can chicken broth
2 cans (4.5 oz) chopped green chilies
1 tsp salt
1 tsp ground cumin
1 tsp dried oregano
1/2 tsp pepper
1/4 tsp cayenne pepper
1 C sour cream
1/2 cup heavy cream (i use half & half)

In large saucepan saute chicken, onion, garlic in oil until chicken is cooked through. Add beans, hominy, broth, chilies, and seasonings. Bring to a boil. Reduce heat & simmer uncovered for 30 minutes. Remove from heat. Add sour cream & heavy cream. Serve immediately.

*You can add a bit of cornstarch to thicken it up