1 cup French green lentils (Lentilles du Puy preferred)

1 tbsp olive oil

1 small onion, finely diced

1 carrot, finely diced

1 celery stalk, finely diced

2 cloves garlic, minced

1 tbsp tomato paste

1 tsp dried thyme or a few sprigs fresh

2½ cups water or vegetable broth

1 tbsp Dijon mustard

1 tsp sherry vinegar (or red wine vinegar)

Salt and pepper, to taste

Optional: chopped parsley for garnish

2 salmon fillets, skin-on

Salt and pepper

Optional: lemon wedges for serving