without so much as (doing) (something)
Without giving or doing something that would normally be expected or considered standard, commonplace, or polite. He barged into the without so much as knocking! They walked out the door without so much as a goodbye.
without so much as
With not even, as in She stormed out without so much as a goodbye. [Mid-1600s]
without so much as something/as doing something
, not so much as something/as doing something
used for emphasizing that somebody does not do something that you expected them to do: She took the money without so much as a thank you.He didn’t so much as look at her when she came in.