Whisk butter and icing sugar with a whisk of the hand mixer until white-creamy. Stir in 1 egg yolk. Mix tea powder, flour and salt, sieve over the butter mixture and fold in. Chill for 10-15 minutes. Form small rolls (approx. 2 cm Ø) from the dough. Whisk 2 egg yolks.
Put brown sugar on a plate. Brush the rolls with egg yolk and turn them in brown sugar. Cut rolls into approx. 0.5 cm thick slices and spread on 2 baking trays lined with baking paper. Bake one after the other in a preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for 12-15 minutes. Take out and let cool down
Waiting time approx. 30 minutes