For shortbread with tonka bean, quickly knead the ingredients into a shortbread dough. Form a roll and refrigerate overnight.
The next day, divide the roll into equal-sized slices, quickly roll them into balls and place them on a baking tray lined with baking paper. Keep each ball two sizes apart from the next ball.
The pattern seen in the photo can be made with my old-fashioned meat tenderizer by pressing it onto each ball. This makes the cookies a little flatter and gives them that pattern. You can of course also take a fork and press the balls flatter with it , then they have a striped pattern.
Bake at 170 degrees top/bottom heat in the already hot (i.e. preheated) oven for about 12 to 15 minutes on the second rack from the bottom.
The shortbread with tonka bean remains quite light on top. But when it becomes light brown on the bottom side it is ready. The recipe makes 2 large baking sheets full.