Sandbakelse, sandbakkels (meaning sand pastry), or sandkaker are a type of a sugar cookie commonly served during Christmas in Norway.
After the dough is mixed and cooled *(our dough from a Norwegian lady was simply to make it like shortbread with room temp butter, press as thin as can into tins and bake), it is pressed into fluted tins.
After ten minutes in the oven, popping the cookies out of the hot tins is best left to adults.
They became popular later than the similar krumkake because sandbakelse required fine flour, which was not yet widely available.
[1] Emigrants took their tins and recipes west across the sea, where sandbakelse remain an "old-country" Christmas tradition for many Norwegian-Americans.