This is a classic German dish, so make sure to serve it with potatoes. The sauerkraut is the most important element. You need to cook it gently and long enough for it to come together, but not too long. If it is overcooked it will turn to mush.

Steps

1. Combine all the sauerkraut ingredients in a medium saucepan. Place over medium heat and bring to a simmer. Cover, reduce the heat, and simmer gently for 1 hour, until the apple is very soft and the liquid in the pan has evaporated.
2. In another saucepan, heat the oil over medium heat and add the onion and salt. Cook gently until tender, about 5 minutes, and add the cloves, juniper berries, and fennel seeds. Cook, stirring, for a few minutes more. Add the beer and chicken stock and bring to a simmer.
3. Pierce the sausages in several places with the tip of a knife and add to the simmering beer mixture. Bring back to a simmer, cover, reduce the heat, and simmer gently until the sausages are thoroughly cooked (small links will take 10 to 15 minutes, larger sausages will take about 30).
4. Distribute the sauerkraut among 4 wide soup bowls. Top with a serving of sausages and drizzle on juice from the pan. Serve with whole-grain mustard and steamed or roasted potatoes on the side.