In a skillet, brown the Ground Sirloin, until completely done, and no pink is left. Drain any excess fat.
Add Onion, and cook until golden brown.
Add Garlic and cook 2 minutes.
In your slow cooker, mix the Shredded Hash-browns, Taco Seasoning, Cheddar Cheese Soup, and Shredded cheese.
Add the Ground Sirloin, and stir together.
Cover, and cook on high for 3 hours, stirring occasionally.
When Casserole is done, serve topped with Shredded Cheese replace lid and allow cheese to melt for 5 minutes, and garnish with chopped green onions. Enjoy!