On Wednesday, October 31, she posted a series of videos letting followers in on the lengthy process, which included prosthetics and heavy green makeup.
This year marked the 19th anniversary of Heidi's annual Halloween bash and she admitted her costumes have grown more elaborate over the years - which can also be risky.
Tom and Heidi also kissed for the "Extra" cameras after he commented, "She looks fantastic".
It seems it was another year of impressive Halloween fun for Klum and all of her friends.
Klum had teased fans that she was working with a prosthetics company to create her costume.
She proceeded to share pictures of her previous costumes on Instagram and Twitter in the days leading up to Halloween, ensuring excitement for the big reveal would reach fever pitch. "I kind of always wanted to be Fiona, but I never had the Shrek to do it with".
Last night, she hosted her 19th annual Halloween party in NY, which predictably was attended by a bagful of stars, including Neil Patrick Harris and Mel B. But with the holiday coming to a close, we can't help but get excited for what she has in store next year.