1¼ cups peeled Garlic, cloves (from about 4 garlic heads)
3 tablespoons Dried Oregano
3 tablespoons White Vinegar
2 tablespoons coarse Kosher Salt, (such as Morton's)
1 tablespoon plus 1½ teaspoons Sazón, with coriander and annatto (such as Badia)
1 tablespoon Adobo, all-purpose seasoning powder with pepper
1 (7-9 pound) bone-in, skin-on Pork Shoulder
3 quarts Water
1 tablespoon plus 2 teaspoons coarse Kosher Salt, (such as Morton's), divided
1 pound uncooked Elbow Macaroni
4 large Eggs
2 cups Heavy Cream
1 teaspoon Seasoned Salt, (such as Lawry's)
1 teaspoon Black Pepper
1½ pounds Sharp Cheddar Cheese, shredded (about 6 cups), divided
Cooking Spray
Process garlic, oregano, vinegar, salt, sazón, and adobo seasoning in a food processor until mixture forms a paste, about 45 seconds, stopping occasionally to scrape down sides of bowl. Alternatively, crush mixture using a mortar and pestle to form a paste.
Using a sharp knife, score pork skin and fat cap about ¼ to ½ inch deep in a diamond pattern, spacing cuts 1¼ inches apart. Cut 8 (2½-inch-deep) slits into bottom and sides of pork. Rub garlic paste over roast, pushing into the slits and scores in fat cap. Place seasoned pork on a rimmed baking sheet; cover tightly with plastic wrap, and refrigerate 4 to 12 hours.
Preheat oven to 350°F with rack in lower third position. Unwrap pork shoulder. Place pork, skin side up, in a medium-size roasting pan; let rest at room temperature while oven preheats. Roast pork, uncovered, in preheated oven until a thermometer inserted in thickest portion of meat registers 200°F, 5 to 7 hours, tenting with aluminum foil after 1 hour and 45 minutes if needed to prevent burning. After about 2 hours of roasting, begin basting pork with pan drippings every hour. Transfer cooked pernil to a cutting board, and let rest 30 minutes. Reserve drippings in pan. Do not turn oven off. Carefully position oven rack in middle of oven.
Bring 3 quarts water to a boil in a large pot over medium-high. Stir in 1 tablespoon kosher salt. Add pasta, and cook according to package directions until al dente. Drain pasta, and rinse well under cold water. Whisk eggs vigorously in a large bowl until frothy, about 1 minute. Whisk in cream, seasoned salt, black pepper, and remaining 2 teaspoons kosher salt. Stir in 5 cups cheese until well combined. Gently fold in cooked pasta. Spoon mixture into a 13x9-inch baking dish lightly coated with cooking spray. Sprinkle evenly with remaining 1 cup cheese. Cover and refrigerate unbaked mac and cheese until pork has finished roasting.
While pernil rests, uncover mac and cheese. Place on middle rack in oven; bake at 350°F until light golden brown on top, about 45 minutes. During final 15 minutes of baking mac and cheese, remove skin from pernil, and finely chop. Shred meat into bite-size pieces. Transfer shredded meat and chopped skin to a large bowl; toss to combine. Discard pork bone, or reserve for stock. Pour pan drippings into a fat separator or a measuring cup; skim and discard fat. Season pernil to taste with skimmed pan drippings. Divide mac and cheese among bowls; top with pernil.