From this teshuva, https://dinonline.org/2010/05/17/berocha-on-ice-cream-with-cookies-inside/
It seems the Rav holds cookie dough is a Mezenos product. I wanted to know why cookie dough is that bracha. Isn’t it raw and not cooked? Shouldn’t it be shehakol? Or do we say that since it is sometimes made to be eaten raw (like in cookiedough icecream) and the process of mixing the flour and other ingridients into a dough makes the product chashuv, the bracha is as if it is cooked and gets a mezonos?
Although the blessing on standard dough is shehakol, if the dough is prepared in such a that renders it suitable for consumption (for instance a doughnut, which is cooked/fried rather than baked), and it is the normal way to eat it in this manner, one would recite a mezonos.
This will apply to cookies in ice cream, provided that there is a significant amount of cookies inside.
If there is only “cookie powder,” which is used as a kind of “spice” for the ice cream, the berachah would be shehakol.
It is therefore possible that different ice creams will therefore be shehakol/mezonos, depending on their texture.
Both berachos are valid bedi’eved.