Step 1

In a large mixing bowl, combine the Earl Grey tea and flour. Whisk together to disperse the tea throughout the flour. Add the salt and confectioners’ sugar. Whisk until well blended.

Step 2

In the bowl of an electric mixer fitted with the paddle attachment, cream the butter for 30 seconds. Add the dry ingredients and mix on low speed. The dough will slowly form as the beater turns. When the dough is well formed it should not be sticky, and it will be thick and clump on the beater.

Step 3

Remove the dough to a piece of plastic wrap and pat into a disk. Refrigerate for 10 minutes.

Step 4

Dust a work surface with flour. Remove the dough from the refrigerator and cut into quarters. Place a quarter on the dusted work surface. Dust the dough and a rolling pin lightly with flour. Roll the piece to a little greater than 1/2-inch thickness. Pick up the dough as you roll to make sure it isn’t sticking to the work surface. If it is, gently prod it loose with a spatula and throw a little more flour underneath it. Lightly re-roll.

Step 5

Use an art brush (or pastry brush) loaded with flour to liberally flour the silicone impression mold. Turn the mat over and tap out excess flour. Lay the rolled dough over the impression mat and press the dough into the cavities with your fingers. Then, use the rolling pin to roll the dough flat to about 1/4 inch. Flip the mold over onto a parchment sheet and gently peel the mold away from the dough revealing a tablet design. Cut away the excess dough from the edges and transfer the molded piece to the freezer to stiffen completely (about 10 minutes). Meanwhile repeat the molding process with the remaining dough.

Step 6

Preheat the oven to 300F.

Step 7

Remove the frozen dough tablets from the freezer and cut into 3-4-inch lengths. Bake the cookies from their frozen state for 20-22 minutes, or until they are very slightly puffed and have a matte surface. The cookies should be pale with the bottom edges very light golden in color.

Step 8

Let the cookies cool on the pans until they are firm enough to move, about 10 minutes. Remove to a wire rack to cool completely. Keep shortbread in an airtight container at room temperature for up to 6 days.