Heat olive oil in a large pot over medium heat. Cook Bratwurst until browned, breaking it up into chunks as it cooks, about 10 minutes.
Stir in onions and garlic, and cook until onions are translucent, about 5 minutes. Mix in fennel seed and sauerkraut with juice, and allow the mixture to pan-fry for 2 minutes without stirring.
Stir in rice and soup base until incorporated, about 2 minutes. Stir in water, raisins, and black pepper. Bring to a boil and cook, stirring frequently, for 5 minutes.
Reduce heat to a simmer, and cook until rice is tender and almost all the water has been absorbed, about 30 minutes.
