Preheat the oven to 400°F
Create the marinade in a large bowl by adding the peeled and chopped garlic cloves, olive oil, maple syrup, and balsamic vinegar. Mix well.
Add the sweet potatoes and Brussels sprouts to the marinade. Mix well until all the vegetables are covered with the marinade.
In a large baking dish, add the sweet potatoes and Brussels mixture. Place in the preheated oven and roast for 20 minutes.
Remove from the oven, and add the cranberries. Mix well and place back in the oven for another 10 minutes.
Serve on the baking dish or serve on a large plate.