Grease a pair of latex gloves with butter and set aside until Step 6.
Line a pair of baking sheets with parchment paper and set them aside.
Add the butter and the marshmallows in a microwave-safe bowl and microwave for 30 seconds each time until the marshmallows and butter melts. Make sure to stir the mixture with a spatula each time.
Once the mixture is completely melted and free of lumps, add in the vanilla and green coloring. Mix with a spatula while you add the coloring until you get the desired green tone. Stir well to spread the coloring all over the mixture.
Once your mixture is all green, add the cornflakes and gently fold them into the mixture. Be very careful to avoid crushing or breaking the flakes.
Put on your latex gloves previously greased with butter and take a small amount of the cornflake mixture in your hands and quickly make a round shape.
Then place it quickly on the sheet with parchment paper and make a hole in the center of the round shape. Form a doughnut shape with your fingers.
Immediately after this, decorate the cornflake wreaths with red candies before the dough hardens.
Let the cornflake wreaths harden at room temperature for 1 hour. (Move your cornflake wreaths to the refrigerator for 30 minutes to speed up the setting process).
Once solid, your cornflake wreaths are ready! Serve and enjoy!