1. Heat olive oil in a sauté pan. Add onions, peeled and chopped carrots, and chopped celery. Cook for 10 minutes. Add wine and let it evaporate.
2. Add rinsed lentils, diced potatoes, and broth. Add bay leaf, parsley, and thyme. Simmer for about 30 minutes, stirring occasionally, adding more broth if necessary so that the lentils are barely covered in liquid.
3. When the lentils and potatoes are tender, lightly mash them to obtain a creamy mixture.
4. Remove the herbs, add heavy cream and spinach. Mix, season, and serve.