I'm trying to make a cookie monster pattern, so I'm watching a lot of video to try and get the shape of his head.
And the more I'm watching him the more I'm wondering if he has any foam to build his head apart from the mouth.

It seems to me the shape of his cranium (with a slight bump behind the eyes) might just be caused by the hand of the puppeteer under the fur.

What do you all think ?

You are correct there is no "skull" inside of Cookie Monster.  Same as the original Kermit.

Side Note: Remember that both of the above characters are copyrighted. It is fine to make one for yourself but you can not make them and sell them or perform with them in public.

Thanks !

Trying to make out his head shape was driving me a bit nuts. It makes more sense now.

So, if there is no foam inside, do you use the fur directly or is it better to back it up with an other fabric ?

You'll need to insert a mouth plate. Do you know what that is?  A mouth plate can be made of cardboard, plastic or even foam. Really no need to back your fur with another fabric.

Yes, I know about the mouthplate. I plan on using a plastic bin lid fo the plate.

I'm still working a bit on the pattern, Cookie's neck on my prototype was not right. But I'm getting there (or at least I hope I do).

My daughter caught a glimpse of the prototype, and even if it is made out of black fleece, with cotton balls for eyes, she screamed "cookie" when she saw it. At least I can count on an easy to please audience

I am sure it'll all work out.  We are always our own worst audience. I'll agonize on something for hours and then it gets on stage and an think to myself... "The audience can't even see what I spent hours working on!".   Still doesn't keep me from doing it again.

What surprised me about cookie was his eyes dangling on pins

Cookie is progressing, the head is done, the body is almost finished.

For the eyes I will paint two christmas ball and pin pupils on it.
But I don't really know how to fix the eyes on the head.

I was thinking of gluing a dowel inside each eye, and then gluing these dowels inside the head. But I'm not so sure about it.
Any suggestion ?

Could work ok.

It might be easier to use a doll joint "backwards".  A doll joint is a plastic nut and bolt of sorts that is used to connect the arms and legs of doll so they can rotate. The shaft of the plastic bolt is normally buried inside the doll but if you place it so it stick out of the top of the head you could glue the eyes to it.

I assume that when you say you are going to use a Christmas ornament for they eye that you mean a Styrofoam one.  If you coat the ornament in a couple layers of papermache' then paint them they are going to hold up a bit better and perhaps hold the paint better.

I see what a dool joint looks like. Great idea, thanks !

For the Christmas ornaments I was thinking about the plastic ones that you can open and fill with wathever you want. Like this: https://www.amazon.com/Plastic-Fillable-Christmas-Ornament-Baubles/dp/B073VLF137

My plan is (was ?) to paint it white inside.