I was at a conference at Caltech. Someone set up boxes of food for lunch. Someone at my table grabbed one and started to eat. I noticed that it said "Stephen Hawking Lunch Gluten Free / Vegan" on it - it was already half-eaten, and I figured it'd be too good an opportunity to pass on, so I decided to eat some of stephen hawking's lunch, literally.

It turns out that despite his physical limitations he actually did eat normal solid foods. This was in 2011.