Out of hundreds of Ganesh shrines in the Valley, the one just in front of Bagalamukhi temple in Patan is very special. Instead of a rodent, Ganesh’s traditionally ‘official’ mount, you’ll find an ox standing guard. Inside the Bagalamukhi temple complex another Ganesh mandir (temple) tells the same story.
The shrine ought to be of Shiva. May be the Shiv Ling is missing.