I'm pretty sure this is clay, but it can be done with fondant.
How to make a crown from fondant
I love this Princess Crown Cake
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tiara template By Misdawn on CakeCentral.com. Where was this the other day when I was making a tiara?!
Mommy and baby Princess Crown Cake How to Make a Pillow Cake
Idee für eine Karte...Pink and white cake, pearls, flowers, roses, crown, heart cutouts, girl
No Bake Chocolate Cheesecake layered with cookies and cream for a delightful dessert that is perfect any night of the week!
Fondant Tiara - Fondant Crown