The Pie throw is a projectile used by Bonker in ClayFighter. Bonker throws a pie as a projectile. This attack requires a quarter circle, which means you have to put your thumb on the down direction of the control pad, then quickly slide your thumb to the forward direction or the backwards direction. Then you have to press the button required to make the move work. In this case, you have to press down forward punch (any strength will do) in order to use this attack. This resembles the sagat's tiger shot from street fighter.
He also has a ground variation called the Cruising pie.