Nona'S Umbrian Lentil Soup - cooking recipe

Ingredients

3 tablespoons extra-virgin olive oil
1 large onion, coarsely chopped
2 garlic cloves, minced
3 medium carrots, coarsely chopped
6 stalks celery, with leaves, coarsely chopped
2 teaspoons dried sage (or 2 whole fresh sage leaves, finely chopped)
1 (14 1/2 ounce) can chopped plum tomatoes, drained
2 cups brown lentils
6 cups vegetable broth
salt
fresh ground black pepper

Preparation

Heat oil in a large skillet over med-high heat; add in onion, garlic, carrots, celery, and sage leaves; saute until the garlic and onion are fragrant, 3-4 minutes.
Add in tomatoes and cook 2-3 minutes to evaporate some of the juices.
Transfer the contents of the skillet to the insert of a 5- to 7-quart slow cooker.
Stir in the lentils and broth.
Cover the cooker and cook on HIGH for 4 hours or on LOW for 7-8 hours, until the lentils are tender.
Check the soup at around 3 or 6 hours to make sure there is enough broth and the soup isn't sticking to the pan; add more broth if it is sticking.
Season with salt and pepper before serving.