Peel and dice sweet potatoes into 1/2" to 1" thick slices
In a small saucepan over medium heat, combine the butter, water, maple syrup, coconut sugar, cinnamon and nutmeg.
Stir until the butter is melted and allow the mixture to come to a gentle boil. Allow to boil for approx 2 minutes without stirring.
Remove from heat and slowly add vanilla. The mixture will be a bit sticky, this is normal and will thin as it cooks in the oven.
Place sweet potatoes in an even layer in a 9x13 prepared baking dish and then pour the sauce mixture over the potatoes. Toss to evenly coat the potatoes
Place in the oven and bake for 20 minutes.
Remove the potatoes from the oven and then cover with aluminum foil and cook for an additional 40 minutes or until potatoes are tender.
Remove the potatoes from the oven and allow to sit for 5-10 minute before serving.