Cafe Rio Pork & Creamy Dressing {copycat}

I know there are tons of recipes out there for copycat Cafe Rio.  I've tried so many variations over the years that I've lost track. But this is by far our favorite Barbacoa pork recipe. We have made it dozens of times over the last 7 or 8 years, and it is still our go to when we are needing a little taste of home. I prefer this recipe to the one that uses salsa, and I think it actually tastes more like the pork you get when you go to the restaurant. Of course, its not a perfect likeness, but its the best one I've found. You can serve this as a burrito, or my favorite, as a salad... either way, you will love it!

Cafe Rio Barbacoa Pork

1 Pork Loin Roast {about 3 lbs}
1/2 Cup Vinegar {I use white}
20 oz. Dr. Pepper or Coke {not diet}
2 1/2 Cups Brown Sugar
1 Grillmates Southwest Seasoning* {found by the taco seasoning or spices}

Cook in crock pot on low for at least 6 hours. Shred and return to crockpot.
Serve with any combination of tortillas**, lettuce, cheese, guacamole, salsa fresca, sour cream, black beans, tortilla strips, cilantro lime rice, cotija cheese, and creamy tomatillo dressing.

*I can't always find the grillmates. I've substituted a packet of fajita seasoning in the past, and it tastes pretty similar. 
**The very best tortillas for this recipe are the tortilla factory brand. You cook them up yourself, and trust me, they are about a million times better. I've found them at Costco, and recently at my local Meijer grocery store. 

Creamy Tomatillo Dressing

1 Buttermilk Ranch Dressing Package {make as per directions... But I halve the mayo and buttermilk}
2 Tomatillos
1/2 Bunch Cilantro
1 Clove Garlic
1 Lime, juiced of
1 Jalapeno {use seeds if you like it spicy}

Place all ingredients in a blender or food processor and blend until no more chunks remain. Serve with Salad.