This feast of earthy flavors will make guests feel welcome. Serve it with grainy mustard, crusty bread, and bottles of dark beer.
Place sauerkraut in a colander set in the sink; rinse with warm water, and drain.
Make bouquet garni: Place peppercorns, coriander seeds, cloves, juniper berries, parsley, thyme, and bay leaves on square of cheesecloth; tie with kitchen twine.
Melt goose fat in very large Dutch oven over medium heat. Add sliced onions; cook, stirring frequently, until onions are translucent but not brown, about 10 minutes.
Add wine, chicken stock, and 2 cups water to Dutch oven; stir to combine. Add dry-salted bacon, smoked bacon, pig's knuckles, pork butt, carrots, garlic, salt, and bouquet garni. Lay washed and drained sauerkraut on top of mixture in Dutch oven. Add enough cold water to bring liquid to 1 inch below sauerkraut. Cover, increase heat to high, and bring liquid to boil. Reduce heat to low; cook at strong simmer for 1 1/2 hours.
Add potatoes; simmer, covered, until potatoes are just becoming tender, about 30 minutes more. Add sausages; simmer, covered, until heated through, about 10 minutes more.
Remove bouquet garni and discard. To serve choucroute garni on platter, remove meat, potatoes, and carrots from Dutch oven. Drain sauerkraut, and place in middle of serving platter. Slice bacon and pork butt. Arrange meat, potatoes, and carrots around sauerkraut on platter.
If some meats are hard to find, such as dry-salted bacon, substitute a more available one, like sausage. Quantity is more important than the exact variety.