Generously season your London broil with salt and pepper, ensuring all sides are covered.

Create small slits in the roast and insert slices of fresh garlic into each slit.

In your crock pot, place half of the sliced onion at the bottom, then add the seasoned London broil on top, followed by the remaining onion slices.

Pour in water and soy sauce or tamari over the meat.

Cover and slow cook on low for 8 to 10 hours.

Once cooked, remove the London broil and let it rest for about 10-15 minutes before slicing against the grain.

For gravy, mix cornstarch with cold water until smooth and whisk into the drippings in a saucepan.