Adjust the oven rack to the middle position, pre-heat the oven to 350ºF (180ºC) and spread 320g (2⅔ cups) of pecans evenly on a large baking sheet. Toast the pecans in the oven for about 8 minutes. Halfway through, take them out of the oven and use a spatula to flip the nuts.

After 8 minutes in the oven, the pecans should smell intensely nutty and be slightly deepened in colour. Allow them to cool completely on the baking sheet.

Once cooled, use a food processor to grind 80g (⅔ cup) of the toasted pecans until they're fairly fine in texture. Coarsely chop the remaining 240g (2 cups) of the toasted pecans, you'll use them for the pecan pie filling. Set aside until needed.

In a large bowl, mix together the softened butter, dark brown sugar and caster/superfine or granulated sugar until well combined. Add the egg, egg yolk and vanilla, and cream everything together until pale and fluffy.

In a separate bowl, whisk together the gluten free flour blend, ground pecans, baking powder, baking soda, xanthan gum and salt, and add them to the wet ingredients. Mix well until you get a smooth, fairly soft cookie dough with no flour clumps.

Chill the cookie dough in the fridge for at least 1 hour or until it’s firm enough to scoop and shape into balls with your hands.

In a large saucepan, whisk together the light brown sugar, golden syrup, eggs, heavy/double cream, vanilla and salt. Cook over medium heat, with constant stirring, until the mixture has thickened and only just comes to a boil. Remove it from the heat and mix in the chopped pecans.

Adjust the oven rack to the middle position, pre-heat the oven to 350ºF (180ºC) and line two large baking sheets with parchment/baking paper. Use a 2-tablespoon cookie or ice cream scoop to scoop out a portion of the cookie dough and roll it between your palms to shape it into a ball.

Place the cookie dough balls onto the lined baking sheets, spacing them as far apart as possible. Bake the cookies for 10-12 minutes or until they've spread and puffed up slightly, and they're evenly golden brown with slightly darker edges.

Immediately out of the oven, while the cookies are still very soft and malleable, you can correct their shape into a more evenly round one. While the cookies are still hot, use a 1-tablespoon measuring spoon to make an indent in the centre of each cookie. Fill the indents with the pecan pie filling.

Allow the cookies to cool completely before serving. If the pecan pie filling has cooled down and thickened too much, you can reheat it briefly until warm.