An apple pie is a fruit pie in which the principal filling ingredient is apple. It is, on occasion, served with whipped cream or ice cream on top, or alongside cheddar cheese. The pastry is generally used top-and-bottom, making it a double-crust pie, the upper crust of which may be a circular shaped crust or a pastry lattice woven of strips; exceptions are deep-dish apple pie with a top crust only, and open-face tarte tatin.