01 -
Adjust the oven rack to the middle position, pre-heat the oven to 180ºC (350ºF) and line two large baking sheets with baking paper.
02 -
In a large bowl, using a wooden spoon, mix together the tahini paste, softened butter, light brown soft sugar and vanilla bean paste until smooth and combined. Note: Do not cream the mixture as that incorporates air which can cause excessive spreading during baking.
03 -
Sift together the gluten free flour blend, cornstarch, xanthan gum and salt, then add to the butter mixture. Mix well with a wooden spoon until the dough starts coming together, then knead by hand until smooth. The dough should not be sticky.
04 -
Chill the dough in the refrigerator for 15-30 minutes to firm it up for easier shaping.
05 -
Divide the dough into two equal portions and shape each into a log about 18 cm (7 inches) in length and about 5 cm (2 inches) in diameter.
06 -
Mix the white and black sesame seeds together on a large plate. Roll each cookie dough log in the sesame seed mixture until well coated.
07 -
Wrap the coated logs tightly in cling film or baking paper, and chill in the refrigerator for about 2 hours or until solid.
08 -
Using a sharp serrated knife, slice the logs into approximately 1 cm (½ inch) thick cookies. Place them onto the lined baking sheets, leaving about 2 cm (¾ inch) of space between each cookie.
09 -
Bake one sheet at a time at 180ºC (350ºF) for about 12 minutes until light golden brown. Keep the second sheet refrigerated while the first batch bakes.
10 -
Immediately after removing from the oven while still hot, you can use a round cookie cutter slightly larger than the cookie diameter to nudge them into a more perfect round shape if necessary.
11 -
Allow the cookies to cool on the baking sheet for 5-10 minutes, then transfer to a wire cooling rack to cool completely.