Here you go...
Onion Dip from Scratch Recipe : Alton Brown : Recipes : Food Network
Make yourself some homemade mayo to go in it, and you are all set.
I like it with part sour cream and part 10% fat greek yoghurt for more tang. But that's a personal preference.
And, yeah... I've been using that recipe WAY longer than I've been Primal.
It's f*king delicious.