Instructions

1. Preheat the oven to 160C/140C/Fan/Gas 3. Line 2 baking trays with baking paper.

2. Sift the icing sugar and cocoa powder into a large bowl.

3. Whisk together the egg, egg whites and vanilla, then carefully stir into the icing sugar mixture to make a smooth batter. Fold in the matzo meal.

4. Place tablespoonfuls of the mixture at least 3cm/1¼in apart on the prepared baking trays. Sprinkle a little sea salt over each. Bake for 15 minutes, until the tops have cracked slightly.

5. Leave the cookies to cool on the baking sheets. Store in an airtight container.