Rinse the lentils and combine them with the carrots, celery, leeks, onion, garlic, bay leaf, and half of the olive oil in a pot.

Saute over medium heat for 5 minutes.

Add the water and cover. Simmer 20 minutes until tender.

Turn off the heat, and add the vinegar.

Preheat the oven to 425 F.

Blend the mustard and remaining olive oil, and spread the mixture onto the salmon fillets.

Place the fillets on a baking rack and cook 8-10 minutes for medium, or to desired doneness.

Stir the parsley into the lentil mixture and divide it among 4 plates.

Place the salmon atop the lentils and serve.