People who feel respected as experts tend to respect their own serious nature more and more. They understand that they can always kid around when they want to, but they don’t have to.- Carol Bly
The way you coax a shy kid out of his shell at school is to give him something to be the expert at. Something he shines at on his own. It’s the same way you sharpen up the class clown.
It’s the same way in the workplace. Find that one talent, that one bit of expert knowledge, that makes a person unique, and then use that to let the person shine. Do it for an entire team, and you soon have this great team of experts who are willing and wanting to share their knowledge.
Of course, make sure they know it’s okay to have some fun while being the “go-to” person for their topic.