Brown the ground beef in a skillet over medium-high heat until it's no longer pink; drain excess grease.
Add the chopped onion and bell pepper to the skillet; sauté until softened (about 5-7 minutes).
Stir in garlic powder, onion powder, black pepper, and salt.
Grease the crockpot if desired. Layer frozen hash browns at the bottom, followed by the beef mixture, undrained diced tomatoes, drained green beans, and corn.
Mix both cans of soup together and pour over the layered ingredients.
Cover and cook on low for 6-8 hours or on high for 3-4 hours until potatoes are tender.
If using cheese, sprinkle it on top during the last half hour of cooking.