- Preheat the oven to 190C. Beat the eggs and sugar until pale and creamy. Stir in the zest of 1 orange and flour, knead until smooth and still a little wet, then roll into logs. Place on greased baking sheets, then bake in a preheated oven for 30 minutes.
- Remove from the oven and slice the logs thinly on the diagonal while still warm. Place the slices on the baking sheet, then return to the oven for 2-3 minutes to dry out. Cool, then store in an airtight container.