1. Heat the oil and garlic in a large pot. Add pancetta, celery, thyme and mushrooms, then cook on medium heat for 4 to 5 minutes, stirring occasionally.
  2. Mix the tomato paste into the pot and cook for 1 minute.
  3. Add lentils, tomato passata and stock, then bring to the boil. Once boiled, reduce heat to a simmer.
  4. Next add the pasta to the pot and cook for 8 to 10 minutes, or until pasta is al dente.
  5. Remove the pot from the heat and cover for 2 minutes. Remove the garlic and thyme, then tear the basil leaves into the pot.
  6. Add salt & pepper to taste.
  7. Finish with pecorino over the top of the soup.