Add flour and cold butter to a food processor and pulse a couple of times until sandy.
Add 2tbsp. cold discard (creme fraîche), cheese, salt & herbs and pulse a few more times until it becomes crumbly and it sticks together if pressed between your fingers. If too dry, add one more tbsp. discard (creme fraîche) and repeat.
Gather the dough together and form into a square - do not knead! Wrap in baking paper and let rest in the fridge for about an hour.
Preheat the oven to 175C, no fan.
On a baking paper dusted with flour, roll the cold dough into a 0,5cm. thick sheet. Cut into small narrow rectangles, brush with a lightly beaten egg and sprinkle with sesame (poppyseeds, sea salt flakes, caraway).
Transfer on an oven tray and bake in the preheated oven, middle rack, for around 20 minutes, or until golden brown on top. Then let cool on the tray. Enjoy as a snak, with tapas or a gazpacho.