01 -
Lightly grease the inside of the crock pot with cooking spray or a small amount of oil.
02 -
In a mixing bowl, whisk together French onion soup mix, beef broth, Worcestershire sauce, and melted butter until fully combined. If a thicker gravy is desired, whisk in cornstarch until smooth.
03 -
Place frozen meatballs directly into the crock pot without thawing.
04 -
Pour the prepared French onion sauce evenly over the meatballs, ensuring thorough coating. Cover with lid and cook on low for 6 to 8 hours or on high for 3 to 4 hours.
05 -
To thicken the gravy further, remove half a cup of liquid, whisk in an additional tablespoon of cornstarch until smooth, then stir back into the crock pot. Cook uncovered for an additional 15 minutes.