Grav Lox with Dill Mustard Sauce

We have been getting wild Alaska salmon at a great price this summer at Costco, and this is a really nice way to have it.

• 1 (2-pound) skin-on, sushi-grade salmon fillet, pin bones removed by fishmonger
• 1 teaspoon caraway seeds
• 1 teaspoon coriander seeds
• 40 grams kosher salt (about 4 tablespoons), plus more for washing salmon
• 25 grams sugar (about 1 tablespoon)
• 1/2 teaspoon freshly ground white pepper or black pepper
• 2 large bunches dill
• For the Sauce:
• 3 tablespoons distilled white vinegar
• 2 tablespoons roughly chopped dill fronds
• 5 tablespoons Dijon mustard
• 1 tablespoon sugar
• 1/4 cup canola or vegetable oil
• Kosher salt and freshly ground black pepper

1. Fill a large bowl with cold water and add enough salt to make it taste like the sea. Add salmon and let stand 10 minutes.
   
2. In a skillet, toast caraway and coriander seeds over high heat, stirring constantly, until fragrant, about 1 minute. Transfer to a spice grinder or mortar and pestle and grind finely.
   
3. In a small bowl, stir together salt, sugar, ground caraway and coriander seeds, and white pepper until thoroughly combined.
   
4. Remove salmon from bath and pat dry with paper towels. On a work surface, turn salmon skin side up and sprinkle about half of salt mixture all over, rubbing in with fingers.
   
5. Arrange half the dill all over the bottom of a baking dish large enough to hold salmon. Set salmon skin side down on bed of dill. Rub remaining salt mixture all over top and sides of salmon, then top with remaining dill. Cover with plastic, then top with a weight (such as a smaller baking dish or plate with cans of beans on top). Refrigerate for 1 day.
   
6. Unpack salmon and turn skin-side up. Re-pack with dill, cover with plastic and set weight back on top. Refrigerate until salmon is sufficiently cured, 1 day longer for a lighter cure and 2 days longer for slightly more cure (slightly firmer texture and saltier flavor).
   
7. For the Sauce: Before serving, make the sauce. In a blender, mini food processor, or using an immersion blender, combine vinegar with dill, mustard, and sugar and blend until dill is very finely chopped. Add oil and blend until a smooth sauce is formed. Season with salt and pepper.
   
8. Unpack salmon, scraping off dill, and set on a work surface. Using a very sharp slicing knife, cut gravlax on the bias into thin slices. Arrange on slices of pumpernickel bread and drizzle sauce on top. Serve. Gravlax can be kept refrigerated tightly wrapped in plastic for approximately 5 days after curing.