Place butter and sugar in the food processor and pulse until they are combined into a creamy paste.
Then add in the lemon juice, lemon zest, cardamom, baking powder, salt and flour and pulse again till well mixed and all the ingredients start forming into big clumps.
Grab a walnut sized portion of the dough between 2 small sheets of baking parchment paper and flatten into an oval shape using your rolling pin. Emma recommends having the cookies at between 5-7mm thick. Repeat till all the dough is shaped into cookies.
Then chill the shaped biscuits for about 30 min. At this stage you can also freeze them for later use.
Pre heat the oven to fan assisted 150 / 170 C/ 340F gas mark.
Lay biscuits on baking tray and bake for between 8-10 mins till they are a lovely pale golden colour.
Remove from oven and let them cool on the baking tray for about 5 mins.
Then carefully transfer them to a cooling rack, cool and then enjoy.
If when rolling out biscuits you find the dough too sticky, pop it into the fridge for about 30 mins to chill it then roll again.