Bring the butter to room temperature. Sift the flour 3 times.
Put the butter in a bowl and knead with a whisk until soft.
Add the sugar in three batches, mixing well with each addition until absorbed.
Add the egg yolk and beat until well-incorporated.
Add the flour and fold with a rubber spatula until no longer powdery. Form into a single ball, wrap in plastic wrap, and chill in the refrigerator for 30 minutes.
Divide the dough into 2 equal portions. Sandwich one portion between two sheets of plastic wrap and use a rolling pin to roll it out to 2 or 3 mm thick (about a 17 cm square).
Line a baking sheet with parchment paper and place the dough on top. Prick holes with a fork (to evenly bake it).
Bake in an oven preheated to 170°C for 10 minutes.
Make the nougat while it bakes
Combine all of the ★ ingredients, except for the coconut syrup, in a small sauce pan, and turn the heat to low. When it begins to boil and thicken, and the color becomes creamy, turn off the heat.
Add the coconut syrup and mix until thoroughly combined. Use a wooden or heat-proof spatula.
Spread it out on top of the hot cookie crust and smooth the surface. It will spread out as it bakes, so leave a boarder of empty space.
Bake in an oven at 170°C for another 10 minutes until it is nicely browned.
Cool until you can handle it, then flip it over and cut with a knife. It's easier to cut it from the back. Once it has completely cooled, you will not be able to cut it well, so be careful.
Story Behind this Recipe
-I recommend making the dough with powdered sugar to make it smooth. -If you have a large oven, spread out the entire amount of the dough, then top with double the amount of nougat, and bake it all together. -I'm afraid of messing it up, so I divided the dough into two batches and baked them separately.