Creating a share of a random shared secret
You probably want a stronger requirement, that no individual knows more than his share. Off the top of my head I don't know how to do that. 

But the question you asked, only requiring no one to know the full secret is easier.
K participants each pick a random number to be their share, using secure multi-party-computation they compute n-k shares which they distribute. 
If n>=2k you compute in groups changing the set of people computing. 

This can probably be modified slightly to meet the stronger requirement without using secure multi party computation as a black box.