Answer:
I'm a small ring shaped fried cake, often with bavarian cream or fruit filling, and sometimes covered in icing and sprinkles.
What instrument can make any sound and be heard but not touched or seen?
What has feet on the inside but not on the outside?
When will water stop running down hill?
Even if you throw it away, it still comes back.
This food is a tortilla filled with cheese and sometimes chicken before being heated or cooked.