I don't remember planting this... could it be somekind of Allium? A. ursinum? I am not sure, will post a photo when it blooms.. it has been 'up' pretty long time already, waiting for the bud to open..
SOLVED: Unknown Bulb
Best way to tell if it is an Allium is to nip the tip of the leaf off and smell it. A ursinum - Ramsons has a very strong oniony smell. I have it in my garden but until it flowers I wouldn't even hazard a guess at species, there are several with broad leaves.