In a bowl, combine the active dry yeast, sugar, and one tablespoon of flour. Pour in about half of the measured warm milk, whisking well to avoid lumps in the yeast mixture. Let stand for 10-15 minutes until bubbles appear on the surface.
Make a smooth, non-sticky dough with the activated yeast starter, flour, remaining lukewarm milk, egg, salt, and lard/or butter.
Grind the pork cracklings and mash them with a spoon to a paste.
Immediately after kneading, roll out the dough on a lightly floured surface into a rectangle about ⅓ inch thick and brush with the ground crackling paste.
Roll it up like a strudel, then fold it lengthwise three times.
Wrap the folded dough in plastic wrap, transfer to a plate and put in the fridge for 30 minutes to rise.
After half an hour, take the dough out, dust it with a little flour, and roll it out gently. Don't roll it too thinly and don't put too much pressure on the rolling pin; otherwise, you will tear the dough and the filling of cracklings will come out. Fold the dough again, wrap it, and put it in the fridge for another 30 minutes.
Repeat the previous step again. In total, the dough will rise for 3x30 minutes.
After the final rise, roll out the dough on a floured surface to about ¾ inch thick. Cut out circles, either with a cookie cutter or a thin-walled glass. The diameter of the cut-outs should be about 2 ½ to 3 inches.
Transfer the biscuits to a baking sheet lined with parchment paper. Cover with a tea towel and leave in a warm place to rise for about 15 minutes.
Meanwhile, preheat the oven to 400°F (200°F). Beat the eggs in a bowl to make the egg wash.
Brush the raised biscuits with egg wash and sprinkle the surface with caraway seeds. Bake in a preheated oven for 15 minutes.