First cook the pasta to al dente according to the package directions. Drain and allow to cool.

Cut the brussels sprouts into very thin pieces, discarding the bottom stems. Core the apple and chop into small cubes.

In a small bowl stir together the mayo, sour cream, vinegar, olive oil, salt, pepper, and dry mustard. In a large bowl combine the pasta, brussels, apple, dried cranberries, and pecans. Drizzle the dressing over everything and toss so it all gets coated in the dressing.