- Melt butter in a medium saucepan over medium-high heat. Add onion to pan; saute 5 minutes or until onion is tender.
- Sprinkle with flour; cook 1 minute, stirring onion mixture constantly.
- Peel, and cut potatoes in cubes, then add in the potatoes, milk, broth, and 1/2 cup water to pan; bring to a boil. Cover, reduce heat, and simmer 10 minutes.
- Add 1/2 cup cheddar cheese and chilli powder; cook 2 minutes or until cheese melts, stirring frequently. Top each serving evenly with 1 1/2 teaspoons chopped green onions.