A pat of butter and a sprinkle of black pepper is all it takes to crown this rich and creamy sweet mash.
In a 4- to 5-quart Dutch oven, melt butter over medium heat. Stir in sweet potatoes, orange juice and maple syrup. Bring to a boil; reduce heat to medium-low. Cover and cook until tender, about 45 minutes.
Remove from heat (do not drain). Mash with potato masher. Stir in mascarpone cheese, orange zest and cardamom. Serve warm.