Place corned beef:
Place the corned beef into the slow cooker with the fat side facing upward.Season with spices:
Season the meat by sprinkling the minced garlic, spice packet, sugar, and pepper over the top and rubbing them in.Add liquids and bay leaf:
Pour the vinegar and add the bay leaf beside the corned beef, then add just enough water so that it reaches about 25% of the meat's height.Cook on low:
Set the slow cooker to low and cook for 8-9 hours.Broil if needed:
If the top of the corned beef is not sufficiently browned after cooking, place it under a broiler positioned 6-7 inches away for 1-2 minutes. Keep the oven door slightly ajar to monitor; do not leave unattended.