Sauerkraut makes a fine topping for sausages just as it is, but its flavor is too strong and sharp to eat more than a few bites. To turn it from a garnish into a meal, you’ll need to cook it. Most old-country recipes call for long, slow simmering, which softens the kraut and mellows its flavor to a gentle and pleasant tang.
Whether it’s homemade or already packaged in a can, a jar or a plastic vacuum-pack, sauerkraut is almost always packed in liquid. That might be its own natural pickling brine, a vinegar solution or even white wine. Some recipes call for cooking the kraut in its packing liquid, while others specifically call for it to be drained and rinsed. There’s no hard and fast rule, so feel free to taste the liquid and see what you think. Keep and use it — or some of it, at least — if it’s palatable, or drain and rinse the kraut if it’s nasty. When in doubt, rinse it out.
Most cooked versions of sauerkraut have a simple starting point. Saute some onions in oil or another cooking fat, then add the drained and rinsed sauerkraut. Add some liquid, roughly 2/3 to 3/4 cup per pound of sauerkraut, and let it simmer gently for an hour or so until it’s soft and mild. The liquid can be anything from plain water to broth, beer, white wine or apple juice, whichever appeals to you.
Naturally sweet or rich ingredients pair well with sauerkraut’s tang, and most recipes go beyond that simple starting point. In the Midwest, for example, onions and kielbasa or bratwurst might go into the pot with your kraut. In Europe, where it’s been a staple for centuries, more lavish versions are common. Germany’s weinkraut and France’s choucroute garnie — basically, “loaded sauerkraut” — turn the lowly cabbage into a show-stopping main dish. You can replicate them at home in a large slow cooker or Dutch oven, or make big batches in your turkey roaster. The basic process is similar, but you’ll use more ingredients and cook it longer.
Saute onions in an oven-safe pot. Add a piece of cured pork. Slab bacon, smoked hocks or the shank end of a ham are all good choices. Many cooks include a piece of fresh pork shoulder or leg, as well.
Coarsely chop a small or medium cooking apple for each pound of sauerkraut, and add that to the pot. Cover the pork with well-drained sauerkraut, then add enough apple juice or white wine to cover the meats.
Flavor the mixture with bay leaves and fresh-ground pepper. European recipes often call for caraway seeds or juniper berries, as well.
After the mixture has simmered in your oven or on your stovetop for an hour or two, add fresh or cured sausages. Simmer for at least another hour, so the sausage flavors are thoroughly infused into the dish. Once the sauerkraut has mellowed and the meats are fork-tender, it’s ready to serve.
Remove the meats and slice or shred them. Fill a serving tray or large bowl with the kraut and arrange the meats on top, and serve it with a bowl of boiled or mashed potatoes.
For an especially deluxe version of the dish, some German recipes simmer heavy cream in a separate pan — often with schnapps, or spices — until it’s reduced to half its original volume. Just before serving, after the meats have been removed, stir the rich cream mixture into the sauerkraut.