That's funny! Out of my three teaching jobs, I have never had a real interview for any of them. I was approached by them and it all came together pretty quickly.
I don't know what my dream job would be exactly. Something where I have the change to make an impact on what matters to me. (Probably in the realm of education).
I usually am very confident in interviews. The way I see it, I want to work for a company that sells green. If I know how to manufacture green, then I will apply or else I may even approach them to tell them about a new shade of green I have come up with that they'll love and that they need desperately. I might even be able to show them how great red is and see if they've ever considered selling it (if that's what I can make) However, if I am a manufacturer of red, then it's really nothing against me if they aren't interested in marketing red. In other words, either I have what they're looking for, or I don't. There is no need to pretend I am anything else than I am, with the skills I have. If they like it, they'll take me. If they don't, we weren't a good fit anyway.
I think it's the same way with dating. People try to make themselves over into the person they think the other person is looking for. Then after about three months, everyone needs to start the whole process all over again getting to know the person each of you actually are. It's so much easier to provide enough information for people to know if you are well suited and move on if you aren't a match. It doesn't mean you are an undateable or defective person. You are just not the right one for them.
If you are truly excited about the kind of work you are applying for, that will come through. You will expose enough information about yourself and want to find out enough about the company you wish to work for quite naturally, so it is fairly quickly determined whether you are a match or not.