In a large skillet on medium high heat, add butter and cooking oil, bring to a sizzle. Add onion and saute until softened.
Add ground beef and cook until thoroughly browned. Drain any excess fat.
Add cream of soup, beef broth, garlic powder, salt & pepper to taste, and mix well.
Turn off heat and mix in vegetables.
Preheat oven to 350 degrees.
Spray a 9x13 casserole dish with cooking spray.
Layer 1/2 the bag of hash browns on bottom of dish. Spoon 1/2 the meat mixture onto hash browns evenly. Place 4 oz of cheddar cheese evenly over meat mixture.
Layer the other 1/2 of hash browns on top of the cheddar cheese. Place rest of meat mixture onto the hash browns. Sprinkle with rest of cheddar cheese.
Cover casserole with foil. (lightly spray with cooking spray the foil if it is not non-stick, to prevent cheese from sticking to foil.)
Place in preheated oven for 45 minutes. Take foil off and cook an additional 15 minutes to lightly brown the cheese. enjoy.
