These these mildly sweet, crisp biscuits — called biscochos de susam, or sometimes just biscochos have their roots in pre-Inquisition Spain. They have become a hallmark of Sephardi cuisine — Middle Eastern Jews bake a similar cookie called kaak. Biscochos are served on Rosh Hashanah (the ring shape symbolizes hopes for a full and round year to come) and also to break the Yom Kippur fast.
 

Recipes adapted from The Jewish Cookbook

• Preheat the oven to 180°C. Line 2 large baking sheets with parchment paper.
• In a medium bowl, whisk together 385g flour, the baking powder, and salt.
• In a stand mixer (or using a handheld electric mixer and a large bowl), beat 2 of the eggs, the oil, sugar, vanilla, and orange zest at medium-high speed until pale and creamy, 2–3 minutes.
• Add the flour mixture in two additions, beating to incorporate and scraping down the sides of the bowl as necessary, until a firm but pliable dough forms. If the dough is too wet or sticky to handle, add up to 35g additional flour, 1 tablespoon at a time as needed, until the desired consistency is reached. (You may not need all of the additional flour.)
• Working on a lightly floured surface, pinch off a walnut- size piece of dough and roll it into a rope that is 15cm long and about 1.25cm thick. Repeat with several more pieces of dough. Using a sharp knife, score little notches about 16mm apart along the length of each of the ropes.
• With the notched edge facing out, form each rope into a ring, gently pressing the ends together to seal.
• Place on the prepared baking sheets. Repeat the rolling, scoring, and shaping process until all of the dough is used.
• In a small bowl, beat the remaining egg. Brush the rings with a little egg (you may not use all of it) and sprinkle generously with sesame seeds. Bake, rotating the sheets front to back halfway through, until the cookies are gently puffed and golden brown, 20–25 minutes. Transfer to wire racks to cool. They will continue to firm up as they cool.