Sometimes over stirring can make them thin.I like them the same way your mom likes them! Thin, crispy edges, chewy center. Mine always turn out kinda soft, thick and cakey and I don't like it.
Oooh thank you! I also read that the amount and kind of sugar used makes a difference in if they spread and how much. I typically don't have brown sugar in the house so that might be why.Sometimes over stirring can make them thin.
Mom's always turns out thin. But I think she leaves the butter out over night which makes them thin out more in the oven because the dough is already warm.
Not creaming the butter and sugar well enough will keep cookies from flattening along with accidently using too much flour via not measuring right. (I read)
Hope this helps.