How to foster gender diversity as an organizer

I am part of the organizing committee for a workshop in a STEM field that historically has problems with underrepresentation of women (and other groups, but let me focus on women in this question). I would like to help foster an inclusive environment at the workshop and more generally in my department and am looking for suggestions for how to proceed.

The topic of the workshop is slightly out of my field of expertise and I do not have a long list of qualified speakers (of any gender) that I can offer suggestions from.

I suspect that the senior member of the committee will take the attitude that he is "gender blind" and chooses speakers to invite based only on their quality but that because of implicit biases, the invitee list he draws up will be something like 90% male. I do not think he will be particularly open to a direct conversation about gender and underrepresentation.

I saw this question which was asking whether preferential invitation of female speakers is normal; I am instead asking how to foster diversity (perhaps by preferential invitation or by other means).