Bring a large pot of salted water to a boil. Add the pasta and boil 8 to 10 minutes or until al dente. Meanwhile, heat the olive oil in a large skillet. Add the chorizo and saute 2 to 3 minutes or until both sides are slightly brown and crisp around the edges. With a slotted spoon transfer sausages to a bowl and set aside. Add the onions, mushrooms and peppers to the remaining fat in the skillet and cook, stirring continuously until the onions and peppers are somewhat tender, about 3 minutes. Add the caraway seeds, water and cooked chorizo. Cover and simmer over low heat until peppers and onions are tender, about 5 to 7 minutes. Stir the mixture on occasion so that it does not scorch. Season to taste with salt and pepper. Drain the pasta and return it to the pot off heat. Add the chorizo mixture and sour cream and toss the ingredients together. Adjust seasoning and serve immediately garnished with parsley.