Traditional Styrian Heidensterz: rustic roasted buckwheat flour scalded with salted boiling water, crumbled into fine buttery morsels in a cast-iron pan, and browned in lard or rich farm butter.
Place the buckwheat flour into a dry, wide heavy cast-iron pan over medium heat. Toast gently for 4 to 5 minutes, stirring continuously, until a fragrant nutty aroma fills the kitchen.
Bring water and salt to a rolling boil. Pour the boiling salted water directly onto the hot roasted flour in one swift motion. A firm steam dumpling will form immediately; do not stir yet, simply cover with a lid and let rest off the heat for 10 minutes to steam through.
Melt the clarified butter or lard in the pan. Using two forks, vigorously shred and tear the steamed buckwheat mass into small, rustic pea-sized crumbs (Sterz). Fry over medium heat for 6 to 8 minutes, tossing frequently until the crumbs turn crisp and golden.
Spoon the hot, crisp buckwheat sterz into shallow ceramic bowls. Serve traditionally with a side mug of cold mountain whole milk or ladle hot mushroom broth directly over the bowl.