Take a large bowl and cream the butter well using an electric mixer for 3 - 4 minutes until the butter is pale.
Add the earl grey tea leaves, salt and cardamom powder in butter. Adding the tea leaves at this step will help to infuse the tea taste better.
Add in the icing powder and beat until mixed together.
Add the sifted all-purpose flour and beat until the texture is crumbly.
Using the hands combine the dough together and work through it until the dough comes together.
Make two logs of the dough (362 grams each) and shape them in the form of a log. The log should be 8 - 9 inch long and 1 ½ - 2 inch wide.
Place the logs in the fridge for 30 minutes or overnight.
Preheat the oven to 350 F.
Take out the logs out of the fridge, cut the logs using a sharp knife to ¼'' wide.
Place the cookies on the baking tray lined with silicone mats.
Bake for 10 - 15 minutes, until the edges are light golden brown.
Take them out and place on wire rack to cool down for 30 minutes.
Lemon Glaze
Combine the icing sugar and lemon juice.
Dip the cookies in the lemon glaze and place on the wire rack for the icing to harden.
Notes
Do not overmix the dough – You would want to knead the dough only until it comes together. Over-mixing will result in tougher cookies.Weigh the ingredients – Weigh the ingredients using a kitchen scale to get the accurate ratio of the ingredients.Chilling is Important – Keep the logs in the fridge and it is an important step. Chilling helps to solidify the butter, which then helps prevention of spreading of the cookies in oven. Chill the dough for at least 30 minutes but you can chill it overnight as well. Chilling of the dough is really important as it solidifies the butter and prevents from cookies to spread during baking.Cool the Cookies - Wait for the Cookies to Cool before dipping them in the lemon glaze or the glaze will not stay on the shortbread cookies.