Sfenj (from the Arabic word Arabic: سفنج, romanized: Safanj, meaning sponge) is a Maghrebi doughnut: a light, spongy ring of dough fried in oil. Sfenj is eaten plain, sprinkled with sugar, or soaked in honey. It is a well-known dish in the Maghreb and is traditionally made and sold early in the morning for breakfast or in the late afternoon accompanied by tea—usually Maghrebi mint tea—or coffee. The term Sfenj is used in Algeria and other parts of the Maghreb. It is called bambalouni in Tunisia, and Sfenz in Libya. In Morocco, the term "Sfenj" is used, also sometimes nicknamed in the literature "Moroccan doughnuts". It is also called Khfaf or ftayr in Algeria, and is sometimes also dubbed as the "Algerian doughnut".

Sfenj originated in Al-Andalus (Moorish Spain). According to legend, Sfenj was created by mistake, when a baker accidentally dropped a ball of dough into a pan of hot oil. Sfenj was an important part of Andalusi culture, whose role was best summarised by a verse from a contemporary poet: "The Sfenj bakers are worth as much as kings" ("سفاجين تحسبهم ملوكا").

It is unclear how Sfenj first spread to the Maghreb, although it is said to have been well known to the Marinid Dynasty, which ruled Morocco from 1270 to 1465. It spread to France during the 13th century, where it inspired beignets. Sfenj were only sweetened with sugar starting in the 18th century, even though sugarcane has been widely cultivated in the Arab world since the 8th century. Before that, they were sweetened with honey or syrup, or simply served plain.

Although Sfenj comes from Al-Andalus, most bakers and sellers of Sfenj in the Maghreb have traditionally been Amazigh (Berbers). The nomadic Amazigh are thought to have spread Sfenj throughout the Maghreb, aided in that by merchants who traveled across the region.

The chef Mustafa an-Nakīr remarks that head meat with Sfenj was a popular breakfast in Marrakesh in his grandparents' time.

Dedicated Sfenj bakers, called sufnāj (سفناج), soon appeared throughout the Maghreb, attesting to the dessert's popularity. Sufnājeen (plural of sufnāj) became central figures in the social life of Maghrebi neighborhoods, as they interacted with almost every household in their community every morning, and working as a sufnāj was considered a respectable career. In a traditional Sfenj bakery, the sufnāj (and their large circular fryer) sit on an elevated platform, raised slightly above the rest of the bakery, which is already raised more than a meter off the ground. Customers surround this platform and try to catch the sufnāj's attention to place their orders by raising their hand at him or her and shouting.

Traditional sufnājeen are quickly going extinct in the modern Maghreb, as a result of the rise of industrial bakeries and the proliferation of Sfenj recipes over the Internet blogosphere.

In addition to ordinary Sfenj, there are two special varieties of Sfenj, not counting the different toppings (honey, syrup, and sugar) Sfenj can have: