Beat the eggs with the sugar until whitened. Add the lard, yoghurt beaten with the ammonium bicarbonate, the juice and grated rind of the lemon, vanilla and flour with baking soda.
Mix everything well and let it sit for 2-3 hours.
Roll out into a sheet 1/2″ (1 cm) thick and cut out bagel shapes, smear them with beaten egg, pour sugar or sesame seeds on top and arrange in a tray smeared with lard.
Bake in a moderate oven.