Finely shred a half head of Red Cabbage and add to a large pot of salted, boiling water. Cover and cook until tender, about 8-10 minutes.
Caramelize diced onion in butter over medium heat until amber, seasoning with salt and pepper.
In a food processor, combine cooked cabbage, onions, and cottage cheese. Pulse briefly to blend.
For the dough, mix Bread flour and All Purpose Flour in a bowl. Add egg and salt, then slowly incorporate water while mixing.
Once a dough forms, switch to a dough hook and knead for about 8 minutes until slightly tacky.
Let the dough rest for 30 minutes covered with a damp towel.
Roll out the dough to about ¼ inch thickness and cut into circles.
Fill each circle with a generous amount of cabbage filling and seal tightly.
Freeze the dumplings on a sheet tray before cooking.
Boil salted water and cook dumplings until they float, about 4-6 minutes.
Pan fry the boiled dumplings in oil and butter until crispy and browned.