I put this together on a chilly, rainy day with items I happened to have on hand. I threw everything in the slow cooker, so it was an easy meal as well as a tasty one. Roasting the sweet potatoes is not strictly necessary, but I think it adds flavor. This is one delicious soup!!
Preheat oven to 450F. Toss the sweet potatoes in enough oil to thoroughly coat. Place on baking tray and roast about 20 min., stirring once, until the potatoes are starting to get some golden brown color on them.
In the meantime, place all remaining ingredients in the slow cooker.
After the sweet potatoes are roasted, add them to the pot. Cook on low for 6-8 hrs. or on high for 4-5.