• Preheat the oven to 180°C (356°F)

Crust

• Add the white rice flour, potato flour, tapioca flour, brown rice flour, xanthan gum, unsalted butter chunks, and granulated white sugar in a food processor. Pulse the ingredients until the butter is well incorporated with the flour. You might still see pieces of butter, and that’s fine.
• Align a 20 x 20 cm (8 x 8 inch) pan with parchment paper and add the shortbread dough. Firmly press the dough onto the bottom of the pan.
• Bake the crust at 180°C (356°F) for 20 minutes or until the edges are slightly golden.

Pecan Toppings

• Add the butter, brown sugar, golden syrup, and cornstarch to a medium-sized saucepan over low-medium heat, and whisk until combined and the butter is completely melted (3-5 minutes). Then set the mixture aside and allow it to cool down to room temperature.
• Once the mixture is cooled, add the eggs, cinnamon, vanilla extract, and whisk until combined. Then add the pecan and gently fold them into the mixture using a spatula.
• Pour the pecan mixture on top of the crust and bake the pecan bars at 180°C (356°F) for another 25-30 minutes or until the center is set. Allow the pecan bars to cool down to room temperature before serving.