Step 1: Prepare the Brine - Mix the water, brown sugar (if using), black peppercorns, red peppercorns, coriander seeds, mustard powder, smoked paprika, garlic powder, and onion powder in a bowl to create the brine.
Step 2: Marinate the Corned Beef - Place the raw corned beef in the resealable plastic bag. Pour the brine over the meat, seal the bag, and refrigerate for at least 5 days.
Step 3: Rinse and Dry - After marination, rinse the corned beef under cold water and pat it dry with paper towels.
Step 4: Prepare for Smoking - Preheat your smoker or grill to 225°F (107°C) and prepare your wood chips for smoking.
Step 5: Smoke the Pastrami - Smoke the corned beef for about 6-8 hours, or until it reaches an internal temperature of 190°F (88°C).
Step 6: Wrap and Rest - Wrap the pastrami in aluminum foil and allow it to rest for at least 30 minutes before slicing.
Step 7: Slice and Serve - Slice the pastrami against the grain and serve on rye bread with mustard or enjoy it as a snack.