Rich sausage and sweet-tart sauteed apples are balanced by the sharp, pungent bite of sauerkraut simmered in hard cider or beer.
Rach uses juniper berries here, which she says are good in any stewed beef or pork dish. Check your spice aisle for them!
Pierce the skins of sausages with tines of a fork in a few places. Place sausages in a skillet in 1 inch of water, bring water to boil, reduce heat to low simmer, and heat through, 5 to 7 minutes.
Heat a large cast-iron pan or heavy deep skillet over medium-high heat. Add ½ tablespoon oil, half a turn of the pan, add the sausages, discard their cooking water, and crisp the casings then remove knocks/sausages and cut each into thirds on the bias.
To large skillet, add the remaining oil, 2 turns of the pan, over medium to medium-high heat. Add onions and apples and season with salt, pepper, seeds, bay leaves and juniper. Stir to soften 5 minutes, add sugar and stir half a minute, add vinegar to evaporate, add beer or hard cider and bring to simmer, then add Worcestershire and sauerkraut. Nest the knockwurst or sausages and simmer over low heat 10 minutes. Top with pickles, herbs and mustard, and serve from the pan with bread and butter or toasted hot dog rolls.