Crunchy oat flake biscuits

Caramelise the oat flakes and the sunflower seeds with the caster sugar cooked to 119°C in 50 g of water. Leave them to cool.
Cream the butter and the sugar, then add the eggs and the yolks. Finish by incorporating the two flours, the caramelised oat flakes and sunflower seeds.
Let the dough rest in the fridge so that it firms up, then roll it out to a thickness of half a centimetre and cut it into discs 4 centimetres in diameter.
Bake at 170° for about 10 minutes (after 7 minutes open the oven door for 10 seconds to let the moisture out)