Pets de sœur, historically translated as nun's farts, is a French Canadian dessert that is made from pie dough; often from left over Tourtière dough, that is layered with butter, brown sugar, then rolled, sliced, placed in a pan, covered with additional brown sugar, and finally baked. It is called Pets de Soeur as it was served by nuns at Catholic schools in some parts of the province of Quebec and Acadia.
In Quebec and French speaking Canada, they are often served during the Christmas holidays and may be served as part of Réveillons; which is a family gathering that occurs on Christmas Eve for Quebecers and French Canadians. Variations may replace the brown sugar with molasses, caramel sauce or maple syrup; however, this is not common nor traditional.