In Lithuanian Christmas tradition, kūčiukai are small poppy-seed pastries served at Kūčios.
Kūčiukai are small, lightly sweetened baked pieces of dough, usually made with yeast and poppy seeds. They are a characteristic food of Kūčios, the Lithuanian Christmas Eve supper held on 24 December.
They may be eaten dry or served with poppy-seed milk. Traditional Kūčios meals are associated with fasting and commonly include multiple meatless dishes, reflecting the older religious character of Christmas Eve.
Kūčiukai are sometimes confused with ordinary cookies because of their small size, but their role is specifically tied to Lithuanian Christmas Eve customs. The name is connected with Kūčios, which derives from the wider regional Christmas Eve tradition.