eating gear
When you're so deep into a meal you're like a hungry dog who just found a bone and won't let go. You might even pretend you're shifting gears on a car just to keep eating.
I was eating so much I forgot my name and started pretending I was driving.
The tacos were so good I did the gear shift thing and said 'I'm not done!'
That cake was so amazing I was like a dog with a bone and wouldn't stop eating.