I just made this with leftovers and it turned out great, so here's the recipe. In my experience, soups are a great way to save leftovers!
Ingredients for 4 (as a maincourse)
2 cups Puy lentils, soaked for 30 minutes in cold water and rinsed
1 onion, peeled and sliced
4 garlic cloves, peeled
4 carrots, peeled and sliced
1/3 cup kombu, rinsed, soaked and chopped
2 dried cayenne peppers, crushed
3 tomatoes, rinsed and sliced
1 teaspoon thyme
1/4 cup minced fresh flat leaf parsley
1 pinch Guerande sea salt (because I'm in France right, now, but any sea salt should work, and I'm sure black salt would be fantastic)
4 teaspoons extra virgin olive oil (optional but lovely)
