Step 1: Rinse the Brisket: Remove the corned beef brisket from its packaging and rinse it thoroughly under cold water. This helps remove excess salt from the curing process, resulting in a more balanced flavor. Pat the brisket dry with paper towels.
Step 2: Prepare the Crock Pot: Place the quartered onion in the bottom of the crock pot. This creates a flavorful base for the brisket and helps prevent it from sticking. Add the carrots and potatoes on top of the onion.
Step 3: Add the Brisket and Spices: Place the rinsed corned beef brisket on top of the vegetables in the crock pot. Sprinkle the spice packet that came with the brisket evenly over the meat. If desired, add an additional teaspoon of black peppercorns for extra flavor.
Step 4: Add Liquid and Vinegar: Pour the beef broth (or water) over the brisket and vegetables, ensuring that the brisket is mostly submerged. Add the apple cider vinegar (if using). The vinegar adds a subtle tanginess that complements the richness of the beef.
Step 5: Slow Cook: Cover the crock pot and cook on low for 8-10 hours, or on high for 4-5 hours. The brisket is done when it is fork-tender and easily pulls apart. Cooking time may vary depending on the size and thickness of the brisket and the specific crock pot used.
Step 6: Add the Cabbage: During the last hour of cooking, add the cabbage wedges to the crock pot. This allows the cabbage to cook until tender-crisp without becoming overly mushy.
Step 7: Rest and Slice: Once the brisket is cooked, remove it from the crock pot and let it rest for 10-15 minutes before slicing against the grain. This allows the juices to redistribute, resulting in a more tender and flavorful final product. Slice the brisket and serve with the cooked vegetables and a spoonful of the cooking liquid.
Optional Tips: To reduce the saltiness of the corned beef even further, the brisket can be soaked in cold water for several hours before cooking, changing the water periodically. For a richer flavor, substitute a dark beer, such as Guinness, for part of the beef broth. Leftover corned beef can be used to make Reuben sandwiches, corned beef hash, or Shepherd's pie.