Prepare all the ingredients.

The day before, prepare the levain: Diluate the yeast in 8 cl warm water.

Pour in a bowl and add enough flour from the total quantity...

...to obtain a soft dough.

Cover the bowl with a cloth and leave it in a warm place until the next day.

The day after: Place this levain in the bowl of a mixer.

Add the rest of flour...

...thinly grated zest...

...sugar, salt, olive oil...

...orange flower water...

...and whole egg.

Begin to knead by adding 10 to 15 cl water ...

...to obtain a flexible dough that does not stick to fingers. Add a bit of water if too hard or a bit of flour if too soft.

Roll the dough into a ball and place in a large salad bowl.

Cover with a cloth...

...and leave to prove 2 hours in a warm place.

Place the dough on a slightly greased baking sheet in the shape of round galette.

Cover and leave to prove another 30 minutes.

Glaze the galette with egg yolk.

Draw square lines using a knife.

Bake in hot oven at 210°C for 45 to 50 minutes.

When finished, leave to cool on a wire rack. Serve warm or cold.