“You need an egg, two spoonfuls of lard, and a pinch of salt, followed by flour, a dash of vinegar, and just enough warm water to create a dough with a dumpling-like consistency.” This is part of the traditional Hungarian strudel recipe that Ilona and Erzsébet, elderly sisters and lifelong baking partners, learned from their late mother. In their small village of Tura, an hour outside of Budapest, the sisters regularly bake the delicate pastry for up to 500 people for weddings and community events.

In the short documentary Strudel Sisters, directed by Peter Hegedus and Jaina Kalifa, Ilona and Erzsébet share how a family tradition evolved into a livelihood. Their quirky rapport may as well be part of the recipe—no strudel-making session is complete without bouts of bickering and singing.

“I loved the sisters from the first time I met them,” Kalifa told me, “and I knew straight away that we had to make a film about them. They are really special people with big hearts and a great sense of humor and just have this warm, grandmotherly feel, which instantly resonated with me.”

Authentic strudel-making is a dying art. It requires a certain moxie: the dough must be worked vigorously in order to activate the gluten, after which it acquires a threshold of elasticity, allowing the baker to stretch it until it’s tissue-thin and nearly translucent. Then, the filling—most commonly grated apple, brown sugar, lemon, and cinnamon—is added intermittently between the pastry layers.

While making the film, Kalifa and Hegedus were lucky enough to taste five different types of the sisters’ strudel. “My personal favorite was the cheese strudel,” said Kalifa. “Strudel is part of their DNA. They’ve been making strudel all their lives, and you can tell.”