Peel, wash and finely slice the vegetables. Peel the onion and prick it with the cloves.
In a casserole dish, brown the Diots on top of all the fillings in olive oil. Remove and reserve them.
Put the vegetables in the still hot casserole and brown them gently.
Add lentils and moisten with water until lentils are covered. Bake for about 40 minutes.
Add the Diots and let cook again for about ten minutes.