Abstract: The present invention provides a dispensing cap for attaching to a container, which includes a dispensing chamber having an interior compartment for holding an ingredient to be dispensed into the container. The top end of the dispensing chamber has a flexible diaphragm and an actuator button and the lower end of the dispensing chamber is connected to a frangible membrane. The dispensing chamber includes a threaded bottle cap for attaching the container to the dispensing cap. A piercing shaft includes a piercing tip and an inclined bottom edge which engages and pierces the frangible membrane at the bottom of the dispensing chamber. This causes the frangible membrane to rupture and thereby form an opening in the bottom of the interior compartment of the dispensing chamber so that the ingredient housed within the compartment freely passes through the dispensing opening and into the container.