Spray inside of a large crock pot with cooking spray. Place pork roast inside. Pour 8 ounces of Coca-Cola (I used a measuring cup) and water around pork. (It does not need to cover roast). Sprinkle evenly with garlic salt, salt and pepper. Cover with lid and cook on High heat for 6 hours, or on Low heat 8-9 hours.
Remove pork from crock pot and transfer to cutting board. Discard liquid from crock pot. Shred pork with two forks, and remove any fat.
In a blender or food processor, blend the remaining 8 ounces Coca-Cola, diced green chilies, enchilada sauce and brown sugar. Blend until smooth.
Place shredded pork back in crock pot. Pour enchilada sauce mixture over the shredded pork. Cover crock pot with lid and cook 2 hours on Low heat.
Heat oil & butter in a large saute pan over medium heat. Add onion and pancetta & cook until onion translucent and pancetta is beginning to crisp. Remove from heat set aside.
Bring a large pot of salted water to boil and cook the linguine to al dente. Drain pasta and return pasta to pot. Heat and add the reserved pancetta and onion mixture. Stir over high heat until pasta is coated with the pancetta mixture.
In a bowl, whisk together the egg yolks & heavy cream and add the pasta, along with Parmesan. Remove the pot from the heat and toss the pasta until it is well-coated. Season with salt and pepper, to taste. If needed, add a bit of the reserved pasta cooking liquid to help toss the pasta if it is dry. Serve immediately.
**I like to add peas to the pancetta and onion mixture.