Place French Earl Grey tea into a small spice grinder or mortar and pestle, and grind until fine. Place into the bowl of a stand mixer fitted with a paddle attachment, along with the caster sugar and lemon zest. Mix on low speed for a minute, until fragrant. Add the butter and vanilla bean paste to the bowl and beat until light and fluffy.

Place the plain flour, semolina and salt into a separate bowl and mix to combine. Add the dry ingredients to the creamed butter mixture, mixing gently until dough comes together. Tip the mixture out onto a lightly floured surface and use your hands to form the dough into a rough rectangle.

Use a rolling pin to roll the dough out between two sheets of baking paper until it is about 5mm thick. Place in the fridge for an hour or so until firm enough to cut. While dough is chilling, preheat oven to 140°C (fan-forced) and line two baking trays with baking paper.

When the dough is ready, use a sharp knife to cut out simple house shapes. About 8 x 5cm is a good size to start with, then cut some smaller and some bigger, until all the dough is used, rerolling offcuts as necessary. Carefully place biscuits onto prepared trays, leaving a little space in between.

Bake in preheated oven for 22-28 minutes or until the biscuits are golden brown and cooked through. Remove from the oven and allow biscuits to cool completely on the trays.

When biscuits are cool, make the icing by whisking the egg white in a medium mixing bowl until frothy. Add the icing sugar and lemon juice and mix thoroughly until smooth. Check the icing is a good consistency to pipe, adding a little more icing sugar or lemon juice as required. Spoon icing into a piping bag fitted with a small plain nozzle (a plastic zip lock bag with the end snipped off works too) and secure end.

Pipe house outlines and details onto biscuits and allow them to set before serving or storing. Iced biscuits will keep in an airtight container at room temperature for up to 2 weeks.