1. Rinse the farro and cook it in boiling salted water for 30 minutes. Drain and set aside.
2. In a large pot, cook the lentils in the vegetable broth until they are swollen and tender.
3. Add the diced potatoes and cook for 20 minutes. Puree the mixture in a blender and return it to the pot.
4. Incorporate the farro and reheat for 10 minutes.
5. Serve with a few spoonfuls of extra virgin olive oil on each serving.