Heat bacon drippings in a large skillet over medium heat. Cook and stir onion in hot bacon drippings until soft and translucent, about 5 minutes.

Place sauerkraut with juice into a large bowl and cover with water. Use your hands to squeeze out as much water and juice as possible. Add squeezed sauerkraut to onion in the skillet.

Stir chicken stock, sherry, brown sugar, and caraway seeds into sauerkraut mixture. Reduce heat to low; simmer, stirring occasionally, until most of the liquid has evaporated, 30 to 40 minutes.