Walnut Croissant Cookies / Crispy and Melt

#croissant #cookies #crispy #delicious
230 g flour
100 gbutter
100 g sour cream
1 egg yolk
5 g baking powder
5 gvanilla sugar
A pinch of salt
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200 g of walnuts
100 g of sugar
1 egg white.
5 g vanilla sugar
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Bake at 180°C for about 20 minutes.