2 year old holding food in his mouth

[singingpinkmonkey]

Hi!
My son turned two yesterday and started a new habit. He has taken to holding food in his mouth and not swallowing. He did it last night with the first mouthful of his tea and is doing it now with his breakfast.
Has anyone heard of it experienced this?
I don't know what to do. It's not because he doesn't like the food we are giving him as they are all the things he likes. He doesn't seem I'll or in any pain. I'm at a loss and am worried that this will become a permanent habit.

Can anyone offer any advice?

Thanks

Mine does this (and when I did a search on here seems its pretty common!). We just tell him its silly to do it and try not to give him any attention for it. Is he generally a good eater? Ours is and can't quite figure out why he does it!