In a large saucepan over low heat, melt the butter. Cook, stirring constantly, until marshmallows are melted.
Remove from the heat and whisk in the food coloring, vanilla, and cornflakes.
Place one or two sheets of waxed paper on the table. Fill a skillet halfway with 1 inch of boiling water. Place the saucepan in the skillet to keep the cookie dough warm.
Drop a heaping tablespoon of cookie dough onto the waxed paper and mold it into a wreath shape with lightly lubricated fingertips. Decorate the cookie right away with red hot candies. Repeat with the remaining cookies to shape and decorate.
Give the cookies fifteen minutes or so to cool to room temperature before taking them from the wax paper. Keep enclosed in a sealed container.