Bring a large pot of lightly salted water to a boil; cook the pasta at a boil until tender yet firm to the bite, about 8 minutes; drain.
Heat oil in a large saucepan over medium heat. Add chicken; cook and stir until juices run clear, 8 to 10 minutes.
Stir chicken broth and paprika into the saucepan. Cook until flavors blend, about 5 minutes. Transfer chicken pieces to a plate. Reserve broth.
Combine half-and-half, sour cream, and flour together in a bowl. Mix until well blended. Add about 1 cup broth from the saucepan; stir until no lumps remain. Whisk mixture into the remaining broth in the saucepan. Whisk in garlic powder, bouillon, and parsley; cook over medium heat until sauce thickens, about 5 minutes.
Stir mushrooms into the sauce; add chicken pieces. Simmer until flavors combine, about 10 minutes. Season with salt and pepper. Serve paprikash on top of the pasta.
