Facebook featured image for site?

I recently switched from wordpress.com to wordpress.org. Everything is up and running but when i go to put a link to my website (www.thecolorfulkitchen.com) on Facebook the preview box doesn’t show a picture. It used to with my old wordpress.com site, and I’m wondering if there is a setting I need to do to set a feature image for the site?

Any advice would be appreciated! Thanks!