Inspired by Balthazar in NYC, salmon is crusted with mustard and breadcrumbs and simply seared, then served over a bed of lentils simmered with carrots, celery, onion and bacon. It's an incredibly simple dish, difficult to mess up, but because it's a classic bistro dish, it has glamour, mystique. A certain je ne sais quoi. —Borrowed Salt
Combine lentils and 4 cups cold water in saucepan. Bring to a simmer, cover and cook for 20 minutes.
In another saucepan, sauté bacon and thyme over medium heat about 2 minutes. Add onion, garlic and salt and cook for 5 minutes until onion is translucent. Add butter, carrots, celery, pepper and 1 cup / 235 mL water and cook for 5 more minutes.
Drain lentils and add to the bacon-veg mixture. Simmer lightly for another 5-10 minutes and lentils are very tender.
Preheat oven to 500F / 260C. Season salmon on both sides. On the rounded side of each filet, spread about 2 Tbs mustard, then press in 1 tsp breadcrumbs to form a crust.
Heat a large ovenproof skillet over medium-high heat and add oil. When oil is shimmering hot, add the salmon, mustard-side down. Lower heat to medium. Sear for 2 minutes, then carefully flip and sear 1 minute more. When flipping, take care to keep the crust from breaking off the fish. Transfer the pan to the oven and cook for 3-4 minutes more, depending on size of salmon.
Serve salmon over a bed of lentils. A simple green salad dressed with a mustard shallot vinaigrette would be a great pairing for a meal.