Preheat oven to 400F. In a large bowl, combine sweet potatoes, cinnamon, turmeric, cayenne, paprika, and olive oil until sweet potatoes are evenly coated. Season sweet potatoes with salt and pepper to taste.
Lay sweet potatoes in a single layer on a large greased baking sheet. Bake sweet potatoes at 400F 20-25 minutes until sweet potatoes are tender. Keep warm until ready to serve (or cool if serving bowls cold)
To assemble harvest grain bowls, divide hot grains between 5 large serving bowls. Arrange sweet potatoes, kale, apples, pecans, cranberries, feta, and rosemary around grains.
Maple Mustard Vinaigrette
In a small bowl, whisk maple syrup, mustard, and apple cider vinegar until smooth. Slowly drizzle in olive oil, while whisking continuously until vinaigrette is smooth. Season vinaigrette with salt and pepper to taste.
Drizzle harvest bowls with vinaigrette and serve warm or cold. Enjoy!