Answer:
Old Mcdonald had this
How do you spell hard water with only three letters?
I'm a small ring shaped fried cake, often with bavarian cream or fruit filling, and sometimes covered in icing and sprinkles.
What has 4 fingers and a thumb, but is not living?
Goliath, The Jolly Green and Andre are all examples of this.
I am the fountain from which no one can drink. For many I am considered a necessary link. Like gold to all I am sought for, but my continued death brings wealth for all to want more.