He was officially sworn in as a Swiss Guard in May 2013. Once he was serving a higher cause, Geisser would hang up his apron and lay his acclaimed chef days to rest.
But during the same time, the Swiss Guard was working on a promotional pamphlet encouraging Swiss Guard prospectives to apply for the position of papal guardian. Geisser jumped on the opportunity to turn the recruit document into a high-quality cookbook, filled with pictures, recipes, and stories.
"The Commander [Daniel Anrig] decided the Swiss Guard should do a cookbook and assigned me to lead the project," Geisser explained, saying Anrig had always been interested in Geisser's culinary background.
Geisser collaborated with Commander Anrig and fellow Swiss Guard Erwin Niederberger, a former pastry chef who produced most of the cookbook's text. Together, they transformed the recruit brochure into Buon Appetito – a culinary masterpiece, carefully crafted with 76 hand-picked recipes, including papal favorites.
Buon Appetito was released in Switzerland in 2014 and critics hailed it as "an instant classic." In 2015, international publishing rights were acquired through the Archangel Company in Cleveland, Ohio and Buon Appetito was transformed into The Vatican Cookbook, released by Sophia Institute Press in April 2016.
The Vatican Cookbook includes additional photos and updated information, as well as an appeal to raise awareness of the Pope Francis-approved campaign, "One Human Family, Food For All." Caritas International is sponsoring the endeavor in an effort to eradicate worldwide hunger, promote improved food production, and reduce food waste across the globe.