You might add a can of petite-diced tomatoes, which will add liquid and contribute to the "Italian" concept. And, yes, add a bit of fresh garlic. You will be surprised at how much natural liquid is produced by the meat. You can use something as inexpensive as chuck roast.
Caution, if you cook it for 18 hours it will literally fall apart. You won't have any chunks.
"As a girl I had zero interest in the stove." - Julia Child
This is real inspiration. Look what Julia became!