Place ham slices in a single layer on the bottom of the slow cooker.
In a mixing bowl, combine brown sugar, pineapple (with juice), and mustard.
Spread pineapple mixture over ham slices in slow cooker.
Cook on low for 5-6 hours or on high for 3 hours.
Notes
You can easily double the recipe to feed more people.
The Dijon mustard is optional, but adds an amazing flavor!
How to turn this into a freezer meal:In a gallon-sized freezer meal bag, add all ingredients. Squeeze out as much air as possible and seal bag closed. Place freezer bag into freezer and it will last 60-90 days. When ready to use, spray inside of slow cooker with non-stick cooking spray. Dump ingredients from bag into slow cooker and add 1/4 cup of chicken broth or water in with the frozen food. Place the lid on top. Cover and cook on LOW heat for 5.5-6.5 hours (or HIGH heat for 3-4 hours).