Melt the butter in a large saucepan over low heat, stirring until fully melted (2-3 minutes).

Add the marshmallows and stir constantly on low heat until completely melted (3-4 minutes).

Remove from heat and stir in the green gel food coloring and vanilla extract until evenly mixed.

Fold in the cornflakes gently until each flake is coated with the green mixture (1-2 minutes).

Transfer to a greased baking dish or parchment paper and shape into a circular wreath approximately 1 inch thick.

Before setting, sprinkle red hot candies and/or red candy-coated chocolates on top for decoration. Allow to set for 15-20 minutes room temperature.