Heat oil in a large, deep pot over a medium-high heat. Add chicken. Cook for 5 minutes, turning occasionally, until lightly browned all over. Remove and set aside. Reduce heat to medium.
Add onion, carrots, celery, turnip, garlic and thyme to pot. Cook for a further 5-7 minutes, stirring occasionally, until lightly browned.
Return chicken to pot with bay leaf, 2 litres (8 cups) water and stock cube. Bring to the boil. Reduce to a simmer and cover with lid. Simmer for 1 hour. Stir in pasta. Simmer, covered, for a further 15 minutes.
Remove from heat. Lift chicken pieces from pot using a slotted spoon. Shred chicken meat and discard bones. Return chicken to pot with parsley. Stir over low heat until hot.