Fry the onion in oil until soft. Add bacon and fry for a minute or two. Stir in garlic and lentils and stir until lentils are covered in oil. Add tomatoes and about a cup of the water or stock. Bring to a boil, then cover and simmer, stirring occasionally. Add more water as the lentils cook, as they absorb a lot.

After an hour of simmering, add zucchini and mushrooms and return to a simmer. You’ll need to taste the lentils to make sure they are soft, but after about 1 ½ hours, they should be done. Test for seasoning—you’ll want to add pepper and stir through chopped parsley.

As a variation, you could add some cumin or other spice and substitute the parsley with coriander.