Preheat oven to 350°F and grease a baking dish.
Cook onion in butter, stir in flour, then whisk in broth, cream, and sour cream.
Add chiles, garlic powder, hot sauce, salt, and pepper. Simmer briefly.
Brown ground beef, season, and drain excess fat.
Layer sliced potatoes, then beef, then pour sauce over.
Top with cheddar cheese, cover, and bake 50 mins.
Uncover and bake 10 mins until golden and bubbly.
