Sweet Potatoes and Marshmallows

Some people make these with whiskey but this a much more benign kid-friendly version. 

8 sweet potatoes
2 tbsp. butter
½  cup hot milk
pinch of salt
½ tsp cinnamon
½ tsp nutmeg
1 cup chopped walnuts
½ lb marshmallows

Cook sweet potatoes until tender. Remove skins and mash.

When smooth, beat in butter, milk, salt, and spices. Fold in walnuts.

Spoon mixture into a buttered baking dish. Top with marshmallows.

Bake at 350°F, 20 minutes or so, checking often, until marshmallows puff and become golden brown.