Preheat oven to 350 degrees.
Mix the melted butter, salt,cayene pepper and cinnamon in a medium bowl. Add the potatoes and toss to coat.
Place the brown sugar in a shallow bowl. Wrap one piece of bacon around a sweet potato cube, secure it with a tooth pick. Roll the bacon wrapped sweet potato cube in the brown sugar so all sides are coated. Repeat for each cube.
Place the cubes on a parchment lined baking sheet, bake 40 - 45 minutes or until bacon is crisp. Cool completely before serving.