cook pasta according to directions on the box then drain and rinse with cold water and add to large bowl
add onion, pickles, cheese, and sliced olives
in a small bowl combine, mayo, mustard, pickle juice, salt, pepper, garlic and onion powder.
mix sauce into pasta and toss
enjoy!
Notes
The pasta will soak up the sauce. Depending on how dry your area is, you may need to make more sauce and add it to your pasta. For instance, here in AZ I have to make 2 batches of sauce. I add the first batch right away and if I am preparing ahead of time I will save the second and add just before the party.