In a large bowl, whisk together soy sauce, honey, garlic, salt, pepper, rosemary, and water.
Place lamb racks in a large bowl and cover with the marinade over top. Make sure the racks are evenly coated.
Let the lamb marinate for at least 30 minutes, up to 24 hours.
When you're ready to cook, place lamb in the bottom of your slow cooker with water.
Cook on the LOW setting for 5-6 hours
Turn the racks 1 or 2 times and spoon the marinade over the lamb.
Use more water if required, just add a tablespoon at a time. (some slow cookers get hotter than others)
Optional, in a preheated oven at 375 degrees F (180 degrees Celcius) for 20 minutes to crisp up the lamb roast.
Using the juices from the slow cooker strain and skim off the fat, this is your Jus.
Serve lamb with Jus, your favorite sides, a drizzle of lemon juice, and chopped fresh herbs. Enjoy!