Melt butter in a large saucepan over low heat. Add marshmallows, and cook until melted, stirring constantly. Remove from heat, and stir in the food coloring, vanilla, and cornflakes. Quickly drop heaping tablespoonfuls of the mixture onto waxed paper, and form into a wreath shape with lightly greased fingers. Immediately decorate with red hot candies. Allow to cool to room temperature before removing from waxed paper, and storing in an airtight container.