Mustacciuoli (also known as mustaccioli or mostaccioli) is a traditional pastries from Naples, usually served at Christmas time.
Mustaccioli takes the form of a parallelogram, and consist of a soft, spiced, cake-like interior, covered in chocolate. In recent years, they are many variations of mostaccioli sold in Naples, where the chocolate glaze may be replaced by a white chocolate frosting or icing sugar and candied fruit. Mustacciolis are often sold alongside other Neapolitan sweets including Roccocò, raffiuoli, susamielli, and struffoli at Christmastime.
The name "mustaccioli" is related to the use of grape must in older recipes (mostacea was the Latin name). Neapolitan mostacciolis were mentioned by Bartolomeo Scappi, personal cook of Pope Pius V as part of his pranzo alli XVIII di ottobre (October 18th lunch).