Candied Yams (Candied Sweet Potatoes)

Candied Yams will forever be a Thanksgiving favorite! This delicious side dish takes just minutes to prepare and the results are phenomenal! Candied Sweet Potatoes are made with brown sugar, maple syrup, butter and cinnamon then baked until perfectly sweet and tender. Marshmallows optional!
3 to 4 pounds sweet potatoes
6 tablespoons unsalted butter melted
1/4 cup maple syrup real maple syrup, not pancake syrup
1 cup dark brown sugar light brown sugar also will work
1 teaspoon ground cinnamon
1 teaspoon vanilla extract
1/2 teaspoon salt
2 cups miniature marshmallows optional