Self-awareness is an essential trait for any leader. One of the cornerstones of emotional intelligence, self-awareness may be the most important skill to master. And it's arguably the most important attribute for a leader who wants to create a culture of growth and development.

With self-awareness, you can probe your emotions in any given situation to understand what you're feeling and why. This is key for understanding how to appropriately respond, rather than impulsively react to a situation going south.

Many executives can tell you their purported flaws or weaknesses. This baseline emotional intelligence is all well and good, but one top CEO I connected with for this article challenges today's leaders to go a bit deeper, and think about self-awareness by boiling it down to one important question:

"Do you really understand yourself?"

Mike Zani, CEO at The Predictive Index and author of The Science of Dream Teams, views self-awareness as a personal journey toward uncovering your dark side -- or to use Zani's preferred analogy, the back of your T-shirt. He credits James Allen, Partner at Bain & Co., with the framework that has not only guided his own self-exploration but framed the behavioral data core to the discipline of talent optimization.

"If you've made it five or six years at Bain, you're already pretty amazing," Zani explains. "So all those amazing things you've been told your entire life? Those are on the front of your T-shirt."

Calling out your 'back of T-shirt' traits

The back of T-shirt traits, however, are less public, and therefore less visible to you. You're aware of all the great stuff because people have told you about it. But you need other people to help you achieve true self-awareness by calling out your back-of-T-shirt traits, as well. Those might include:

• Playing favorites with colleagues
• Being an inconsistent listener
• Steamrolling others with your own ideas
• Misjudging your own humor or charm

These traits are your bugaboos. They manifest in ways people notice (and probably chafe at), and they're holding you back from that big leap in personal development.

True leadership requires an act of certain courage -- a willingness to peel back the onion and own your uglier layers. In doing so, you'll create a safe space for your peers to help.

"That entails going on a journey of self-awareness to see what's back there -- and your perspective on this is actually one of the worst," Zani says.

Many people have trouble acknowledging the flaws in their own perspective, and as a result, they can't truly own their back of T-shirt traits. Commitment requires openness and vulnerability, but also certain levels of curiosity and humility.

"It's human nature to take these traits and minimize them, or externalize them, to say 'Oh that was the situation.' To say: 'Well, whenever a jerk walks in the room, I become a bigger jerk. Well, maybe you're the original jerk.'"

Digging for personal development

For Zani, the decision to take the journey was an easy choice. He wanted to retain and develop people -- the greatest business asset -- rather than lose them. By committing to his own journey, he also improved his ability to coach and interview others, because his own vulnerability either prompted an equal response or, as he puts it, "BS answers."

But along the way, he was forced to learn some not-so-flattering things about himself. It's not that Zani's back-of-T-shirt traits were any more egregious than yours or mine, but the exploration required him to unpack their triggers.

He realized he wasn't the best listener in certain situations, and even when colleagues would share good ideas, he might drift into his own ideas and lose his focus. It took peers telling him -- and then agreeing among each other -- that this was a theme, for him to accept their feedback. From there, he went to work on those triggers.

"You can feel those triggers coming, you can remove yourself from a situation, and you can be your best," Zani explains. "You can also coach others, because you've taken the journey yourself and you have a framework from which to talk about it."

That's huge because it promotes not only your own personal development but that of your entire organization.

Taming your triggers

If you can get to the point where you not only recognize, but neutralize your triggers, the trickle-down effect will be massive. People will see that you're working on something (yourself), and they'll be more inclined to assume positive intent. They'll get onboard with you. And in doing so, you'll promote leadership at every level.

The most effective method is to enlist your colleagues. That means opening yourself up to scrutiny -- through 360 reviews, engagement surveys, and other forms of potentially stinging feedback -- but the payoff will be worth it.

"If you create a culture of openness and transparency, you'll establish trust and awareness at the organizational level," Zani says. "You'll be much more likely to give people the benefit of the doubt, and more chances -- because you know they're working on it. Instead of chafing at them, you'll want to support them."