[It] became very difficult, almost to the point where it kind of crippled the writing process. I was agonizing over whether I was doing it right and obsessed with this notion that women live in a different emotional arena. At some point I just let go and I began to view these two women, not as Afghan women, but rather just people and focused on their humanity rather than their femininity. Suddenly a really transformative thing happened. These women began to speak for themselves, and I kind of became a mouthpiece for them rather than me speaking through them. The novel almost wrote itself after that.
— Khaled Hosseini

That's from an interview with Hosseini in Time, which you can read here. There's also a video online somewhere. I have a small issue with what Hosseini said, which I'm going to talk about.

I'm starting with that not to disparage Hosseini, who is a more talented and accomplished writer than I will ever be (and he chooses to write about women in Afghanistan rather than vampires in the developed world.) However, a friend linked the interview to me a few years ago, as the majority of what I write is from a woman's perspective, and has been to an extent as far as I can remember. My friend also spoke about the difficulty of writing female characters, and I admit that I don't really see what the issue is.

I'll be honest. My first thought when Hosseini said the above was that he seemed to spend a while coming to the idea that women are people, not weird creatures that exist "in a different emotional arena."

The writer Kate Elliot says it better than I can in her post at Tor.com:

Write all characters as human beings in all their glorious complexity and contradiction.
— http://www.tor.com/blogs/2015/03/writing-women-characters-as-human-beings

It's a nice post. Go and read it. She also makes a great point about simply putting more women in your stories, as protagonists or background characters or whatever, and have them interact.

Women aren't a collection of gendered traits any more than men are, and bad writing relies on stereotypes and cliché. These things sound obvious, but it's amazing how hung up people can get on writing any character other than a straight cisgender man.

Write some characters as women. Change some genders around. It's amazing how little you have to do.

People's behavior and personalities are not necessarily dictated by their gender. They can be, but that's an authorial choice that we should own. The protagonist of my current work-in-progress is a British Bangladeshi ex-Muslim, and although her background forms part of her story and character arc (which is entirely my choice), she's first and foremost a human being (kind of - she is a vampire!) with needs and desires and problems and flaws. I don't want to sit down and think, "what would this ex-Muslim of South Asian ancestry do in this situation?" I'd rather approach it as, "what would Fareena Khan do in this situation?"

In many ways, Rachel was an easier character for me to write than any of the men in the story (i.e. Jacques and Hashimoto), as her personality is closer to mine. Write a character enough to get in their head and, when they start speaking to you in their voice, the words will flow.

None of the above means you can't make mistakes, though, so I'll leave you with part of an email from a good friend and early Rachel beta reader, Kyra Weaver:

One last nitpick: you don’t have to describe every single woman’s breasts when you introduce their character, Dob.

Thanks for the tip, Kyra! She also has a blog about life in Japan right here!