- 8 garlic cloves, finely chopped
- 1/4 cup olive oil
- 3 tablespoons whole grain mustard
- 3 tablespoons light brown sugar
- 2 tablespoons kosher salt
- 2 teaspoons freshly ground black pepper
- 2 teaspoons oregano leaves, finely chopped
- 1 1/2 teaspoons smoked paprika
- 1 skinless, boneless pork shoulder roast, tied (Boston butt; about 6 pounds)
- 1 large shallot, finely chopped
- 2 cups basil leaves, finely chopped
- 1 1/4 cups extra virgin olive oil
- 1/4 cup oregano leaves, finely chopped
- 1 teaspoon crushed red pepper flakes
- 1 teaspoon kosher salt
- 1/2 cup fresh lemon juice
- A (4-quart) slow cooker
- Cook the pork: Mix garlic, oil, mustard, brown sugar, salt, pepper, oregano, and paprika in a small bowl to form a paste. Rub all over pork, then transfer to a resealable plastic bag or slow cooker insert and chill overnight.
- Place pork in slow cooker, cover, and cook on low until meat is fork-tender but not yet completely falling apart, 7 1/2–8 hours.
- Meanwhile, make the sauce: Mix shallot, basil, oil, oregano, red pepper flakes, and salt in an airtight container. Cover and let rest up to 3 hours at temperature or up to 2 days in refrigerator. Stir in lemon juice just before using.
- Transfer pork to a cutting board and let rest 5 minutes. Slice and transfer to a platter. Drizzle with sauce and serve with additional sauce alongside.
- Pork can be rubbed 2 days ahead; chill in an airtight container. Sauce, without lemon juice, can be made 2 days ahead; chill in an airtight container.