I've usually got enough outdoor lighting at the house for all my needs, but at a competition, you never know what conditions you may be cooking under, so I'm with Winz on the headlamp.
I have LED rope lights I string up around my popups, and I've had these LED BBQ lights (sorry about the pics) for a few years and they also work great.
I think they are Perfect Flame, and I got them at bLowes. Strong dual magnet and screw clamp base keeps them secure. 2 AA battery.
Use them with my Backwoods and they provide a lot of illumination.