These are edited excerpts from the conversation.

In your opening monologue for “Saturday Night Live,” you made light of your work as a longstanding character actor. Does it bother you, that designation?

We were making fun of my persona. I’m not a household name like Brad Pitt. People like to have labels for actors, and the truth is, every actor is a character actor. When I say actor, I mean actresses as well. Toni Collette is a good example of someone who can do both leading lady and transformational characters, where you’re barely recognizing them. I think Billy Crudup, Chris Walken, Robert De Niro, they’re all great examples of that.

People often use the word “quirky” to describe your characters. Do they all have to be iterations of you?

I think in every character you’re finding a version of yourself. I don’t relate to racism, because I wasn’t brought up that way. I can relate to self-loathing. The reason a person lashes out the way Dixon does is because he hates himself, so anybody can relate to that. I’m drawn to complex characters; they’re all filled with so many different feelings, and that’s what makes them interesting. The first “Iron Man,” Tony Stark, was an interesting character. He drinks too much, he’s a womanizer, and then he has this epiphany. That’s what’s interesting.

What do you think it was about this role, and this film, that led to so many awards?

It’s the transformational aspect of it, the fact that he was really many different roles wrapped up in one role. He’s a doofus, he’s a racist, he’s violent, he’s a mama’s boy. There’s a few heroic things at certain points. But he’s very flawed, and it’s a boy-to-man journey.