Mix all the meatloaf ingredients in a large bowl. (if you have time, which you probably don’t, you can sauté the diced onion. Totally optional and will taste great either way.)
Form into a loaf to fit the slow cooker. Place a strip of foil under the meatloaf to make it easier to place in and remove from the crock.
In a smaller bowl, mix all of the ingredients for the sauce.
Once you have the meat formed in the slow cooker, cover the top of the meatloaf with the sauce.
Cover. Cook on low for 6-8 hours.
Notes
Optional: Give this recipe a try next time you need dinner prepared in advance. Bon Appétit!