The only difference I can tell is that Dolly's is a bit thicker. So I would suggest softening the cream cheese a bit, but only to the point where is is easily workable to mix with the sour cream. In fact, if you get the "whipped cream cheese spread" and just let is set out a bit, it would probably be great for this. I'd also probably take out the milk part, as that only thins it out more.

I personally don't like onions much, so I used 1 tsp of Onion Powder and 1 and a half tsp of Garlic Powder.

IT IS SO YUMMY!!!! I still love Dolly's, but now I can have creamy cheese dip no matter where we get pizza from! Yay! Thank you again! =)