Is there anyone knwoing about the math and chemistry behind
cookie-baking for Christmas?

What do scientists say?

They should not be too hard, they should not be too soft, they should
not crumble.

I think baking is really complex and maybe some scientists may had the
time to find the "perfect-cookie-formula"

Because I loose about 30% of my cookies every Christmas because nobody
can eat them and I must feed them to the birds.