I've only seen people taking challah from the dough if they are baking bread or matzah. I noticed this question that addresses fried dough (e.g. some types of donuts.)
Would one need to take challah if he is making wafers, cookies or cakes?
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Star K says:
When kneading dough for baking pas haba’ah b’kisnin (e.g. cake and cookies), for boiling (e.g. noodles), or for frying, one is mafrish Challah if 2.6 lbs. (82/3 cups) of flour are used. A bracha is not recited even if more than 5 lbs. of flour are used.
He bases his opinion on Aruch Hashulchan Y.D. 329
I should mention that the term "pas haba’ah b’kisnin" is quite ambiguous and includes what are commonly called "mezonot rolls". This dough usually contains a large volume of fruit juice, and, thus, may not be considered "hamotzi" bread according to some opinions. The article addresses taking challah from such dough mixtures.