Don't do this when the oven is on unless you want to get as burned as bad as you usually burn those cookies! While the oven is off though, this is a great exercise to improve your ab strength and give you more stability in your trunk and low back.
Sit on the floor with your legs out in front of you and arms up on the oven bar. Use that oven bar to stabilize as you bring your legs up towards your head, creating a V with your body. Try to keep your stomach tight, go slow and keep your back flat. Repeat until those abs are burning and then get back to cooking so you don't burn the food too!