Brown ground beef and cool slightly.
In a large bowl, stir together soup, evaporated milk, garlic, and seasonings.
Add the chopped onion and mixed vegetables.
Add cooled beef and mix gently.
Add tater tots and mix again. Spoon mixture into a large (gallon) freezer bag.
Place the shredded cheese in a medium freezer bag.
Remove the excess air from both bags, seal, and staple together above the fold.
Dump the contents of the large bag into the slow cooker. Cook on high for 3-4 hours or 6 hours on low.
Place contents of the large bag in a 9x13 casserole dish. Top with cheese. Bake at 400° for 30 minutes.