Step 1Cook the pasta in a large pot of boiling, salted water until al dente, 10 to 12 minutes. Rinse, drain and set aside.
Step 2Meanwhile, in a large bowl, combine the crab, mayonnaise, buttermilk, onions, lemon juice, onion powder, garlic, seasoned salt, parsley and pepper to taste. Add the pasta shells and mix again. Cover and chill overnight.