1 1/2 teaspoons whole coriander seed 
1 1/2 teaspoons whole cumin seed 
1 1/2 teaspoons black peppercorns 
2 1/4 teaspoons coarse kosher salt 
1 1/2 teaspoons dry mustard powder 
1 1/2 teaspoons chili powder 
3 tablespoons dark brown sugar 
3 1/2 pounds boneless pork shoulder 
Hamburger buns, for serving

In a dry, small skillet over medium-low heat, toast coriander, cumin and peppercorns until fragrant, 1 to 2 minutes. Using a spice grinder or mortar and pestle, grind toasted spices into a fine powder. Transfer to a bowl and mix with salt, mustard powder, chili powder and sugar. If your roast is tied up, untie it. Massage meat generously with spice rub. If you have time, let meat rest for an hour or two at room temperature, or refrigerate for several hours or overnight.

Heat oven to 300 degrees. Place pork in a baking pan and roast for 3 to 4 hours, uncovered, or until meat is pull-apart tender and internal temperature reads 200 degrees on a meat thermometer. Let meat cool for at least 30 minutes before pulling it apart and shredding with your hands or two forks. This works best when the meat is warm but not hot. The warmer the meat, the easier the pulling.

Serve pulled pork with coleslaw and barbecue sauce layered on buns.