Prep

Preheat oven to 325°F (165°C) and line a baking sheet with parchment.

Bloom the zest

Before mixing, rub the lemon zest into the sugar until fragrant. This releases the oils and gives a noticeably stronger lemon flavour throughout.

Make the dough

Whisk eggs, egg yolk, melted butter, vanilla, and lemon juice, then add the zest-infused sugar and dry ingredients. Combine into a sticky dough, then fold in dried blueberries and white chocolate chips if using.

Shape

Divide into 2 logs. With lightly floured or dampened hands, flatten each to about 1 inch thick. (Founders’ Note: This dough is really sticky - for this step, flour a cutting board or counter and your hands!)

First bake

Bake at 325°F for 25–30 minutes until set and lightly golden. Cool 10–15 minutes before slicing.

Slice

Using a serrated knife, cut on a slight diagonal, about ½ - ¾ of an inch thick.

Second bake

Reduce oven to 300°F (150°C). Bake 8 minutes, flip, then bake another 5–7 minutes. You want crisp edges with a slight tenderness inside — pull them before they feel fully dry.

Glaze

Whisk icing sugar with lemon juice until smooth. Drizzle over fully cooled biscotti. Add a pinch of zest to the glaze for extra brightness.