Gently clean the roe, removing all blood and tissue but making sure not to break the membrane. Place the cod roe on a sheet of parchment paper and season with about 2 teaspoons of the salt. Place the bay leaves and 2 lemon wedges on top. Fold the paper gently around the cod roe, as if you were wrapping a fragile present, and tie up the package with a piece of kitchen twine.
In a large pot, bring 4 quarts water to a boil. Add the remaining salt and the vinegar. Add the cod roe, reduce the heat, and simmer gently for 35 minutes. Lift the package out of water and let cool.
Unwrap the cod roe. Remove and discard the bay leaves and lemon. With a sharp thin knife, cut the roe into thin slices. If you are serving this as an appetizer, transfer the roe to plates and season with pepper. Garnish with the sour cream, chives, and Cucumber Salad. If serving as canapés, place a slice of roe on each cracker, season with pepper, and top with the salad, sour cream, and chives. Arrange on a platter, garnish with remaining lemon slices, and serve.