Chrissy Teigen's not one to get iced out of the fun ... so she took the pastry bag into her own hands to add the finishing touches to her daughter Luna's birthday cake.
We got Chrissy at Duff's Cakemix in West Hollywood ... looking like she's having a blast through the window. She tells us decorating it was easy too.
It's hard to see, but we're told the cake had a little 1 on top. Luna's birthday is a couple weeks away ... so Chrissy and John Legend must be celebrating early.