I didn't manage to snap a picture of the inside of the cake due to all the birthday fun but I used the pitaya powder to create an ombre effect throughout the layers. (greensofthestoneage.com)
Buy some cool patches and sew them on at odd angles, or get some metallic spray paint and create an ombre effect over the damaged area. (cosmopolitan.com)
Using a whisk, gently blend the spirulina on the surface, moving it toward the opposite side of the bowl to create an ombre effect. (cravethebenefits.com)