CLASSIC MINESTRONE

This is from a book called "Eating for Lower Cholesterol" by Catherine Jones. I haven't yet made this, or the next few recipes, but I need to return the book to the library, so I am posting the recipes I want here so I can find them again.

3 tablespoons olive or canola oil
1 onion, finely chopped
2 garlic cloves, crushed
2 carrots, peeled and sliced (or 1 cup sliced baby carrots)
1 cup thinly sliced leeks
1 medium potato, peeled and small diced
2 celery stalks, thinly sliced
2 teaspoons dried oregano
1 medium zucchini, small diced
1 cup frozen green peas
1 cup great northern beans, rinsed and drained
8 cups fat free low-sodium stock
3/4 cup ditalini pasta, or other small pasta
1 can (14.5oz) diced tomatoes
salt and pepper

Heat oil in large pan over medium-high heat. Add onion and saute, then add garlic, carrots, leeks, potato, celery and oregano and saute for 3 minutes, stirring constantly. Add zucchini, peas, beans and stock and bring to boil. Reduce heat and simmer uncovered for 5 minutes.
Add pasta and tomatoes and simmer 10 minutes.
Adjust seasoning, add more stock if soup is too thick.
Garnish with chopped basil and parmesan if required.