Rinse salmon filet and pat dry with paper towels. Lay skin side down in a small pan or deep dish. Pour lemon juice over top, covering the whole filet.
In a small bowl, mix the salt, sugar, cilantro, parsley, and shallot. Sprinkle mixture over top fish. Cover tightly with plastic wrap and place in refrigerator for 2 days.
In a small pan combine molasses, bay leaves and cayenne and bring to a quick simmer, then remove from heat and allow to cool. In a small skillet, lightly toast the caraway and coriander seeds over moderate heat, shaking the pan, until fragrant, about 1 minute. Transfer the seeds to a mortar and let cool completely. Crush the seeds as finely as possible with a pestle. Stir in the paprika and ground pepper.
Scrape the seasonings off the gravlax and place on the same cleaned out deep dish or another one, skin side down. Brush the top with the glaze, remove the bay leaves, then sprinkle with spices. Refrigerate uncovered for about 12 hours.
Slice thin and enjoy or wrap tight and save for up to 1 week.