In a large pan, heat oil over a medium heat until hot. Add ham and gently fry, stirring occasionally, until browned, about 3 minutes.
Stir in leek, celery, mushrooms, carrot and garlic. Cover and saute for 5 minutes, shaking pan occasionally while in contact with heat.
Add stock, pepper, savoury and bay leaves, stir well. Bring to the boil. Add split peas and barley, return to the boil. Reduce heat to medium-low, cover and simmer, stirring occasionally, until peas and barley are tender, about 50 minutes. Remove bay leaves. Stir in chopped parsely. Ladle soup into serving bowls. Serve.