By Steve Beck

PHILADELPHIA (CBS) — Archbishop Vincenzo Paglia, President of the Vatican’s Pontifical Council for the Family, spent Monday in Philadelphia and brought his sweet tooth.

Archbishop Paglia was in Philadelphia as part of a one-day planning visit for the World Meeting of Families, that will bring Pope Francis to Philadelphia this coming September.

During his visit, Archbishop Paglia stopped by the Potbelly Sandwich Shop located at 17th and Market Streets in Center City. While at the business, Archbishop Paglia, along with help from students of Saint Peter the Apostle School in Philadelphia, selected a special edition milkshake that is being created to support the World Meeting of Families.

The winning milkshake?

It’s called #PopeInPhilly,” which is a hand-spun combination of vanilla ice cream and Shortbread butter cookies.

The winning milkshake will be sold at all three Philadelphia Potbelly Sandwich Shops from April 1, 2015 to September 30, 2015.

Fifty cents from every milkshake sold will be donated to the World Meeting of Families.