Cream butter, sugar and salt. Stir in egg, 1 egg yolk, lemon peel and butter- vanilla flavouring. Mix flour, almonds and baking powder, add and knead everything into a soft dough. Form 2 rolls of the dough, each about 20 cm long. Wrap in foil and chill for about 2 hours. Cut rolls into slices of approx. 1.5 cm and roll them into strands of approx. 18 cm in length.
Form into pretzels and spread them on 2 baking trays lined with baking paper. Mix the remaining egg yolk and 1 teaspoon of water. Brush the pretzels with this mixture and sprinkle with sugar crystals. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for 10-12 minutes. Let them cool down