I get all my ingredients for this at Wal-Mart. Runs me about $9, and is enough to either share, or feast on for days (it very nearly fills a five-quart pot).

1 16-oz box Garden Rotini
1 16-oz box Whole Wheat Penne
2 12.5-oz cans of pre-cooked chicken
1 15-oz can of peas (for color and texture)
1 16-oz bottle of Zesty Italian
1 16-oz bottle of Ranch, or a variant of it (e.g., chipotle, bacon)

Chill the dressing, peas, and meat in the fridge, in advance. (I usually allow at least an overnight, and 24 hours if I can plan ahead.)

Cook both boxes of pasta, per package directions, in the same 5-quart pot. (Tip: Go a little crazy with the salt, when you're cooking the pasta here. You won't notice the flavor if you use too much, but you will DEFINITELY notice the texture if you use too little.) Drain pasta, rinse, return to the pot, cover, and put the whole thing in the fridge to chill.

Once everything is sufficiently chilled, drain the canned ingredients, combine everything (pasta, chicken, peas, and both bottles of dressing) in the pot, mix thoroughly, and serve.

Refrigerate any leftovers...if there are any!