- 1 skinless, boneless pork shoulder (Boston butt; about 6 pounds)
- Kosher salt
- 1 tablespoon black peppercorns
- 1 tablespoon coriander seeds
- 1 tablespoon crushed red pepper flakes
- 1 tablespoon dried oregano
- 1 tablespoon yellow mustard seeds
- 1/2 cup olive oil
- 6 garlic cloves, peeled, crushed
- 1 tablespoon finely grated lemon zest
- 2 teaspoons smoked paprika
- Special equipment: A spice mill or mortar and pestle
- Using the tip of a knife, lightly score fatty side of pork; season all over with salt.
- Coarsely grind peppercorns, coriander, red pepper flakes, oregano, and mustard seeds in spice mill or with mortar and pestle; set spice mixture aside.
- Heat oil in a small saucepan over low heat; add garlic and cook, stirring, until fragrant and barely golden, about 5 minutes. Stir in lemon zest, paprika, and reserved spice mixture. Let marinade cool.
- Rub marinade all over pork, working some marinade into interior of roast. Tie pork at 1″ intervals with kitchen twine. Wrap tightly in plastic and chill at least 8 hours.
- Let pork sit at room temperature 1 hour.
- Preheat oven to 375°F. Unwrap pork, place on a rack set inside a roasting pan, and roast until golden brown and fat has just started to render, 40–50 minutes. Reduce oven temperature to 300°F and continue to roast until meat is very tender, 1 1/2–2 hours longer.
- Transfer pork to a cutting board and let rest 30 minutes before slicing.
- DO AHEAD: Marinade can be made 1 week ahead; cover and chill. Pork can be seasoned 3 days ahead; keep chilled.