Into a slow cooker pour in the beef broth, Worcestershire sauce, tamari, dijon mustard, garlic powder, onion powder, and salt & pepper, to taste. Whisk together.
Pour in the frozen meatballs and stir them together.
Set the slow cooker to High and cook for 2 hours. After 2 hours, whisk vigorously for 30-40 seconds.
Combine evaporated milk in a measuring cup with the cornstarch. Whisk to combine and then pour into the slow cooker. Cook on High with the lid off for 30 minutes, or until the sauce thickens.
Enjoy as a meal or appetizer!
Recipe by our friend Taylor @Taylorgolub