Start by peeling the onion. Use a sharp knife to cut it into coarse cubes, about half an inch in size. This size will help the onion cook evenly and add flavor to the sauerkraut.
Next, gather your spices: take the juniper berries, cloves, black peppercorns, and allspice berries, and place them in a spice bag or a small tea infuser. This will make it easier to remove them later.
In a large pot, heat the lard over medium heat. If you don’t have lard, unsalted butter works well as a substitute. Once the fat is hot and melted, add the chopped onion to the pot. Stir the onion pieces occasionally with a wooden spoon or spatula. You want the onions to become soft and translucent, which should take about 5-7 minutes.
After the onions are cooked, carefully take the pot off the heat to prevent any splattering. Gently add the raw sauerkraut to the pot. Use two forks to fluff the sauerkraut, breaking up any clumps and mixing it with the onions. This will help distribute the flavors evenly. Once the sauerkraut is incorporated, place the pot back on the heat. Stir everything together well.
Now, add a pinch of sugar to the pot. The sugar will help balance the acidity of the sauerkraut. Carefully place the spice bag or tea infuser with the spices into the pot, making sure they are covered by the sauerkraut. Reduce the heat to low, allowing the sauerkraut to simmer gently.
Cover the pot with a lid and let it cook for about 60 minutes. During this time, you can occasionally stir it to ensure even cooking.
If you want to enhance the flavor, you can add a little vegetable broth or dry white wine during the cooking process, especially if the sauerkraut seems too dry.
After 60 minutes, check the sauerkraut for tenderness. It should be soft but still retain some texture. If you used bacon, you can add it in now, either diced or as whole strips, depending on your preference. Stir everything together and let it simmer for an additional 10-15 minutes, allowing the flavors to meld.