First melt the butter in a saucepan, then add the sugar and caramelize until light brown while stirring constantly. Remove the pan from the heat and immediately stir in the flour and salt. Let the caramel dough cool for about 10 minutes, stirring again and again.
In this condition, it should be a firm kneadable dough. If the dough is too crumbly, add a little milk. Now stir in the eggs and baking soda, so that a viscous dough is formed.
Put a teaspoon of dough on the baking sheet. These flow widely and double their size when baking, so make sure there is enough space between them.
Bake the biscuits in a preheated oven at 190 ° C for nine minutes.
After removing the biscuits, let them cool a little before removing them from the baking sheet, as they break very easily.