Heat the fan oven to 180°. Peel and finely chop the carrot and celery. Peel and finely chop the onion, then place all the ingredients in a saucepan with the extra virgin olive oil; sauté for around 10 minutes. In the meantime, heat the stock. Add the Valfrutta dried Giant Lentils - Classic Products range (completely drained) to the sauté and pour in all the stock. Cook for around 10-20 minutes, then place around 4 spoonfuls of lentils (without liquid) in a dish. Add plenty of paprika to the lentils set aside and mix. Line a baking tray with baking paper and add the lentils and paprika (spread out and separated) and the bread (cut into small cubes, with oil, salt and pepper). Cook for around 10 minutes, taking care not to burn. When the lentils in the saucepan are cooked al dente, add the Valfrutta Spinach and cook for a further 10 minutes to mix all the ingredients together thoroughly. Serve the soup garnished with bread cubes, the lentils with paprika and the crumbled Feta cheese.